Thứ Năm, 30 tháng 8, 2018

Waching daily Aug 30 2018

A question for you- have you ever played the game "telephone?"

You know, the game where someone whispers something to someone and then that person

whispers it to someone else and then that person whispers it to someone else…and by

the time you get through everyone playing, the original message is all messed up?

I used to kind of dread that game---most people seemed to like it---but somehow whenever it

reached me, the message was always really messed up so I felt like I was spreading nonsense.

Well, either that, or it was me all along that misheard it.

Anyway, the game is all about communication and how things spread.

Communication is incredibly important not just for us but for the things that we are

made up of.

Like our cells!

Cells make up all living things.

And while they don't talk in the way that you and I do, it's important for their messages---their

signaling---to be transmitted and received appropriately.

Multicellular organisms need their many cells to be able to work together to carry out functions.

Just consider all of the cells working together in one of your organs—like you heart—for

example!

First some vocabulary---we're going to be talking a lot about receptors.

A receptor is a molecule---such as a protein---where a signal molecule can bind.

One place you can find receptors is on the surface of a cell membrane.

When a signal molecule binds the receptor, amazing things can happen.

The receptor might start activating another molecule for an action to happen---the receptor

often changes its shape slightly in the process---more about that later.

So receptor.

Signal molecule.

The signal molecule can be considered a ligand, a fancy term which basically means it's

the smaller molecule that binds to a typically larger molecule.

Signal molecules can be a variety of things such as gas molecules or hydrophobic biomolecules

like lipids or hydrophilic biomolecules like some kinds of proteins.

But ligands are generally smaller than the receptors they bind.

Ligands and receptors can have a very specific fit as well.

Let's talk about the general sequence of cell signaling.

First, Reception.

Typically, a signal molecule binds a receptor.

Second, Transduction.

The receptor gets activated by this binding.

This often means the receptor will change its shape.

It could even involve a whole series of molecules changing their conformation in something called

a signal transduction pathway.

This can amplify the original signal.

Third, Response.

There is some kind of response that is going to happen.

A portion of DNA that is found in the nucleus getting transcribed for example, that's

a type of response.

Now cell signaling can involve intracellular signaling---which occurs within the cell itself---

and intercellular signaling where a cell communicates with another cell.

In many cases, signaling involves both: signaling between cells and then also the signaling

within cells.

Now, when we're talking about signals traveling from one cell to another--- distance matters.

Some cells are close and have direct contact.

In the case of these two animal cells, they are gap junction close.

Gap junctions in these animal cells---or plasmodesmata in plant cells---are connections between two

close together cells that can allow ions or other small molecules to pass and by doing

so, they don't have to pass across the plasma membrane.

Paracrine signaling allows a cell to target another cell by a signal molecule that may

diffuse between them---these cells are still close---but need not be connected.

The ligands in paracrine signaling tend to be rapidly reabsorbed and rapidly degraded;

the ligands are typically not traveling far as this is local signaling.

Synaptic signaling which specifically involves neurotransmitters in a synapse is another

example of this local signaling.

And what about long distance?

Endocrine signaling can allow a cell to communicate with a target cell from far away.

Signals may be carried in the bloodstream.

Hormones released by certain types of endocrine cells are a great example.

We also want to point out that a cell could just signal itself.

For example, in autocrine signaling, a cell could secrete a certain type of molecule which

then binds to its own receptor and causes a response.

A cell releasing its own growth factor could be an example of this.

Let's just give a few signaling examples so we can get a basic understanding of the

vocab and what this can look like.

Let's say we have a steroid hormone that travels through the cell's semi-permeable

membrane.

Remember that would mean the steroid hormone is our signal molecule, our ligand.

Once inside the cell, it binds a protein receptor within the cell.

Now the protein receptor is active.

The protein receptor travels into the nucleus where the cell's DNA is found.

This protein receptor binds to DNA and is involved in getting transcription of a certain

gene going, which eventually can be used to produce a specific protein.

This is an example of signaling inside the cell, simplified a bit.

Now in that example, the receptor was inside the cell, a cytoplasmic receptor.

But it doesn't have to be.

Receptors are frequently part of the cell's membrane surface.

If a receptor is sitting outside on the cell membrane surface, then the ligand doesn't

have to come in.

In fact, there could be properties of the ligand that may not allow it to pass the membrane:

the ligand could be hydrophilic which would make it hard to pass through.

Let's mention an example of a cell surface receptor type: a ligand-gated ion channel.

Ions normally don't go unassisted through the cell membrane --- they are charged after

all --- see our cell transport video.

But a ligand-gated ion channel gives them a way through---through a channel!

But it is controlled.

In this example, the channel is closed.

But here comes a signal molecule, a ligand, it binds the receptor---which is the channel

protein in this case.

Now the channel protein responds by opening.

The ions - not the ligand- go through.

Once ions get through, the concentration of ions increases inside the cell.

And you may wonder, "Ok, so now there are ions in the cell, why does that matter?"

Well the increasing ion concentration can trigger a cellular response.

After reaching a certain concentration and stimulating a cell response, the ligand can

leave its binding site from the receptor and the channel can close.

Ligand gated ion channels can be used by neurons--- a neurotransmitter may be the ligand for the

channel to open.

This could happen at a synapse.

But just be aware that not all ion channels are ligand-gated ion channels.

Ion channels can be gated by other things.

A voltage gated ion channel, for example, depends on electrical membrane potential---not

a ligand.

Voltage gated ion channels are used by neurons too.

Check out action potential in neurons to learn more.

There are other types of cell membrane surface receptors we don't have time to go into

in this video.

G-protein linked receptors and enzyme linked receptors are two other types that we encourage

you to explore!

So, in summary, why do we care about this cell signaling thing?

Well, realize that your body processes that keep you alive rely on your cells' ability

of cell signaling.

From the regulation of your heartbeat to the hormone signals traveling long distances in

your body to the ways the neurons in your brain communicate---your multicellular self

needs cell signaling.

But there are many disorders where cell signaling does not work as it should and so understanding

all of the complexities of cell signaling is critical in order to find ways to treat

them.

Cancer is an example of a disease that can involve body cells with problems in cell signaling.

When we mentioned autocrine signaling – a cancer cell could have a problem where it

produces too much of its own growth factor causing excessive division.

Cancer cells can also have many other cell signaling difficulties where they do not function

like normal, healthy cells.

Or another example, there are also pathogens – such as viruses or bacteria – that can

take advantage of cell signaling.

Consider the virus HIV which targets Helper T cells.

Helper T cells are important immune cells in your body, and they have something called

a CD4 receptor on their surface.

That receptor is important so that Helper T cells can communicate with other immune

cells.

But as mentioned in our viruses video, HIV targets that CD4 receptor.

It is because of the virus binding to that receptor on Helper T cells that the virus

can attach and infect the cell in the first place.

A fact that continues to be researched for treatment options.

The understanding of the details of cell signaling continues to expand.

Well that's it for the Amoeba Sisters, and we remind you to stay curious.

For more infomation >> Intro to Cell Signaling - Duration: 8:59.

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4- His humility | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:31.

For more infomation >> 4- His humility | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:31.

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Avengers 4 GALACTUS Is The Power Stone REVEALED!? You Won't See This Coming! - Duration: 7:44.

voted into existence and the remnants of

these systems were forged into

concentrated ingots infinity stone he

stones it seems can only be brandished

by things of extraordinary strength

observe these carriers can use the stone

to mow down entire civilizations like

wheat in a field once what a moment that

group was able to share the energy

amongst themselves but even they were

quickly destroyed by it

what is good youtube Warstu here with a

video on Avengers 4 so it's coming up to

September that's when the infinity war

blu-ray officially comes out over here

so I'm starting my giveaway on this

video I'm gonna be giving away up to

three at least one so all you got to do

is subscribe to the channel make sure to

like share and comment down below who is

your favorite MTU villain and why so

today's video is insane and it's come

from a fellow youtuber who I speak to

called the cosmic Wonder don't worry I

spoke to him back going over this theory

and he okayed it so he's a fellow

youtuber in the Marvel creator community

that we have here pretty awesome dude

so yesterday post an insane theory which

makes a lot of sense about Galactus

being the Power Stone or trapped in the

past own so make sure to subscribe to

him guys the link will be down below and

he's also been on my recommended channel

list for a while so guys make sure to

subscribe

so yesterday I posted a video about the

Infinity Gauntlet snack waking up or

creating Galactus inside with a quantum

well but what if this isn't true and he

is in fact the power stone like this

video just say so ages ago there was a

theory are going around about the

finalists Easter Egg from guardians of

the galaxy B and Galactus inside the

celestial staff because of the helmet

but it was debunked by James Gunn

now James Gunn has nothing to do a

Marvel because they fired him due to

what was going on we don't know what the

final Easter Egg is ever going to be

although some people say it was

confirmed it wasn't really confirmed he

debunked it so the theory is Galactus is

the power stone or is trapped in the

Power Stone but to answer this question

you have to know what the infinitive

Infinity stones are throughout the whole

m2u we've learned a band from various

people in this video from the theory

I've said and where it's come from Odin

and the collector mainly are the sources

of information

our relics that predate the universe

itself what lies within

so in dark world

Odin said there were relics that predate

the universe itself then in gardens that

galaxy the collector went into more

detail about the creation itself there

were six singularities then the universe

exploded into existence and the remnants

of the system will forge into

concentrated in Gong's aka leo infinity

stone so in the flash there are remnants

there's time remnants when you

manipulate the timeline manipulate a

universe and kind of do stuff you're not

supposed to do it so that's not really

relevant to this I just thought it's

kind of funny that as remnants in the

MCU and there's remnants inside the

flashy universe so what this theory is

saying is both Odin and that the

collector said that these relics existed

before our own universe existed and when

it exploded these relics left from these

universe and the remnants pieces all

fought into Infinity stones hence why

they are so strong this is how and why

the Infinity stones were actually

created so how this theory worked is

really due to the origin of collectors

himself the lion who gained cosmic

abilities by passing a near star and

then the character was further developed

revealing that Galan lived during the

previous universe that existed prior to

the Big Bang which begun the current

universe as client universe became to an

end he merged with a Centon of the

universe to become Galactus an entity

that wielded such cosmic power as to

require devouring entire planets to

obtain his existence he's essentially a

source of power he is the power who is

Galactus the world eater

so the Galactus came before the current

universe before the Big Bang his

universe was wiped out and he could be a

remnant from the universe which could

easily be one of the six six seven six

six

singularities that we spoke about the

MCU and Marvel Comics aren't exactly the

same but Marvel directors like the Russo

brothers who made infinity war civil war

an event

for like to pull from the comic but the

Russo brothers pacifically won't carbon

copy anything from the comics but they

will take Emperor inspiration and they

will modify a story or talent in

different way so the power stone angle

actors are the same color we see this in

the gardens the galaxy Easter egg with a

celestial and that's why most people

think that is the last Easter egg which

is interesting during the flashback we

see a celestial with what looks like the

Power Stone and the helmet looks like

practice helmet wiping out a whole

planet which shows the true power of

Galactus the world here and obviously

their similarities so if you follow this

video the idea that Galactus could

either being a Power Stone or be stuck

in that the Power Stone makes a lot of

sense but who could have actually

brought them in there I'm not sure in

the comics it was the watcher so maybe

they could do it and here so I don't

know guys it would be a really

interesting concept I know what some

people would say but would you the fox

deal hasn't gone through well yeah he is

part of the Fantastic Four and that kind

of stuff but you never know they might

have a secret deal like I said in

yesterday's video that could allow

Galactus to be SERP for the Avengers 5

overall villain he could appear it could

be a little cheeky Easter Egg telling

you oh my god Galactus is stuck in the

Power Stone you got remember cuz we

never seen the Power Stone get taken did

we it got took from Xander but that

scene got deleted did it get deleted

because of the hole he is Galactus stuck

in the Power Stone I think it's very

interesting so guys I like I said that

the style video make sure to check out

the original video from the cosmic

Wonder is links in the bio it's also in

the community and I sorry it's also in

the feature channels at the left at the

right off the top of the channel so guys

would love to know what you think about

his theory I think it would be insane I

know - like this videos back to back I

am working on an Adam warlock video I

think there is a way the Adam warlock

was secretly inside infinity war and

Avengers 4 so I'm posting that later on

if I've got time should be posting it a

couple of hours after this two or three

hours out of this

if I get time so I call his guys check

out the competition let me know who's

the best MCU villain ever and don't you

say that offs please please because we

want a nice low-key jokes anyway guys

please like subscribe and comment and I

will catch you in another video very

soon catch you

For more infomation >> Avengers 4 GALACTUS Is The Power Stone REVEALED!? You Won't See This Coming! - Duration: 7:44.

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True Mitsubishi Eclipse CROSS 2019 - Duration: 7:47.

Autobloggers start to make their projects

I thought why me, who make

some projects half of my life

do not start doing reviews

I made a review for eclipse cross

Well, does it open here?

and it is without an electric motor

this is the eighteenth year now

wacky machine

incomprehensible to anyone especially by name

I understand if it was called an outlander

all would perfectly understand the outlander cross

everybody approve it looks like an outlander

called as outlander but eclipse

Use the Eclipse name for crossover - this is nonsense

I made review for it

but after a while i can't

live with thought that I did not criticize it

It is necessary to tell the truth what kind of car it is

and how it should looks like

in real, that's why I made my ECLIPSE CROSS

this one

[music]

in my opinion this is eclipse and this is

eclipse CROSS

I do not know budgets of mitsubishi

for the construction of new machines

but even I can do an automatic transmission

all-wheel drive, front-wheel drive

rear-wheel drive

mechanical transmission with the same options

this is a mechanical 6-speed Transmission

from mitsubishi evolution

it already was installed on this eclipse

since I made it all-wheel drive

in general, it was the first AWD conversion

of eclipse of 4th generation

in the world

unfortunately it is not released

from the factory with all-wheel drive option

[music]

Also it's possible to build it with

the automatic transmissionon, with the five-step modern automatic transmission

I do not understand why mitsubishi

do not produce now automatic transmissions

for them everything is expensive

but since I'm talking about full drive

the most important part of the all-wheel drive car

this is the rear transmission

in mitsubishi eclipse CROSS same transmission as in outlander

but I think the owners of the outlander

perfectly understand me - this is not the best

mitsubishi decision in last years

it is easy become overheated it does not hold anything

it's always turns off. Well, in general this

not my option! my version is - cast iron!

a real "true" rear DIFF which

hold any loads

there is a block 1.5way

disk block with the possibility I do not know what

Well, there it should be

in connection with this reducer, you can

use several different

transfer transmissions mitsubishi

this is an option with interaxle diff lock

and the front axle diff lock

You can also know this system as

electronic lock system

of the differential - ACD

but all of these systems, all diff locks

all full drives and transmissions are not important

without a powerful heart

this is not 1.5L turbo is a real 3.8L mivec

in the atmospheric version of this engine

we have 300 HP.

but we are YouTubers. we are building eclipse cross

so, this two turbines

allow us get

hmm.. 500 HP, not less

we are making offroad car. we are making cross

eclipse CROSS and the most important

parameter is a clearance

[music]

[music]

[music]

all reviewers check clearance

by cigarette box

let's try

i think it's not our version

40 cm till spar!!! enough???

as the result we have "true"

mitsubishi eclipse cross 3.8 L

all wheel drive transmission

as manual

and also automatic, diff locks of all axles

big read clearance

offroad options

yes, it's not crossover but this is eclipse and this eclipse is a "true"

cross in my opinion, but not in the minds of mitsubishi

mitsubishi learn

how to make cars

till we made this review i thought

we can really make this project

build this MONSTER

it's depend on you my followers

as each youtuber i'm mercantile

if followers want cross - let's CROSS

followers want Concept RA

by the way link in the description of this body kit

let's build concept RA

so please write your comments

depends on your opinion

destiny of this project. To build or not to build

Subscribe, put likes

call the bess, Ciao!

[music]

no, you must give it to me

this is left hand if you see

can you raise it up?

[music]

[laughing]

[music]

For more infomation >> True Mitsubishi Eclipse CROSS 2019 - Duration: 7:47.

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KAMOU SAVAGE " A La Francaise" ( Clip Officiel ) - Duration: 2:07.

For more infomation >> KAMOU SAVAGE " A La Francaise" ( Clip Officiel ) - Duration: 2:07.

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Сергій Юрченко Батьківський поріг (аudio) - Duration: 3:05.

For more infomation >> Сергій Юрченко Батьківський поріг (аudio) - Duration: 3:05.

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31- His integration as an immigrant | responding to Wilders' #MuhammadCartoonContest | Soliman - Duration: 0:53.

For more infomation >> 31- His integration as an immigrant | responding to Wilders' #MuhammadCartoonContest | Soliman - Duration: 0:53.

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22- His modesty | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:55.

For more infomation >> 22- His modesty | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:55.

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1 How to respond to Islamophobes?| responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:41.

For more infomation >> 1 How to respond to Islamophobes?| responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:41.

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How Are We Searching For Dark Matter? And How Do We Even Know It's Real? - Duration: 16:02.

Whenever I mention dark matter in anyway in the Guide to Space, or in a questions show,

I get a bunch of responses that have essentially the same point.

Astronomers are just speculating, why do they even think dark matter is a thing?

They're sure going to be embarrassed in the future when they realize they were wasting

all this time.

Oh, astronomers.

Foolish, gullible astronomers.

The reality, of course, is that many astronomers have dedicated their lives to the mystery

of dark matter.

More than a decade of school, working with incredibly complicated math, and then many

more years of observations, using some of the most powerful and sensitive instruments

ever designed by human beings.

And obviously I know that people can spend their lives dedicated to nonsense.

So in this video I want to do two things.

First, I'm going to spend some time explaining how astronomers realized that dark matter

is something real.

In fact, the evidence is overwhelming, and I'm going to get into it.

And then I'm going to talk about the fascinating work going on around the world to search for

dark matter.

What are the individual experiments, observatories and projects which are trying to chip away

at this mystery.

Before I go further into this dark matter.

I want to give you an analogy that comes from my Astronomy Cast co-host, Dr. Pamela Gay.

Because I don't think that most people really understand the state of the search for dark

matter.

Let's imagine you're driving your car and it starts to make a knocking sound.

You take it into the mechanic and they can't figure out what's causing it.

They ask you to drive some more in different conditions and maybe you can help located

the problem.

You realize that it only makes the sound when you're going up a hill and turning left.

You bring back this new information to the mechanic and this gives them a better place

to search for the source of the problem.

If some friend ridiculed you because of your "dark knocking sound", all they'd have

to do is spend a little time in your car and they'd hear the sound too.

The problem is definitely there, it's just that you and the mechanic haven't figured

out what's causing it yet.

But you will, oh… you will.

You have a mystery, and you haven't solved it yet.

That's dark matter.

And dark energy is an stranger mystery, but that's a topic for another video.

I think the name "dark matter" is probably the source of the confusion.

It should have been called something like invisible matter, or mystery matter, or crazy

gravity, or… something.

Okay, back to dark matter, and let's start with a brief history.

I'd like to thank Dr. Brian Koberlein for his comprehensive history of dark matter on

his blog.

I'll put a link in the shownotes so you can learn more about it.

The effect of dark matter was first discovered by the astronomers Fritz Zwicky, who was studying

the motion of galaxies in the Coma Cluster.

Located about 321 million light-years from Earth, this cluster contains more than 1,000

separate galaxies.

During his study of the cluster in 1933, Zwicky calculated that the motion of all the galaxies

was too fast for the gravitational interactions of the galaxies themselves.

There had to be some kind of missing mass that was contributing to their movement.

Of course, it's possible that the individual galaxies happened to be flying past each other,

but the same result was found in all the galaxy clusters that astronomers could locate.

The next key piece of evidence came with the way that galaxies themselves rotate.

Think about the way that planets orbit the Sun.

Each planet goes at a different speed depending on its distance from the Sun.

Mercury completes an orbit every 88 days, while Earth takes 365 days and Pluto takes

248 years.

You would expect the stars within a galaxy to do the same thing.

Stars close to the center of the galaxy whip around quickly, while the ones in the outskirts

take their time.

Through her pioneering work of measuring the rotation rates of individual stars in distant

galaxies, Vera Rubin figured out that spiral galaxies rotated like disks.

All the stars moved the same speed around the galactic center.

One idea, of course, was that there was some kind of hidden matter, like the dark nebula

we can see here in the Milky Way.

These block the light from a more distant object, hiding it from our point of view.

But astronomers developed techniques to measure the radio signals coming from these dark clouds

of matter, and the amounts in galaxies didn't account for the amount of mass it would take

to make galaxies and galaxy clusters behave the way they do.

Astronomers were left with two possibilities.

Either their understanding of gravity at the largest scales was wrong.

This idea was known as Modified Newtonian Dynamics, or MOND.

As long as you were willing to put in new equations for gravity, you could predict the

kind of motions observed in nature.

The other idea was that there was some kind of invisible particle.

A particle that accounts for the vast majority of the mass in the Universe, but it doesn't

interact with regular matter in any way we can detect, apart from gravity.

These were known as Weakly Interacting Massive Particles.

In order to better map out the dark matter in the Universe, astronomers used a technique

called gravitational lensing.

This is where the gravity from a foreground object, like a galaxy cluster, distorts the

light from a more distant object, like another galaxy cluster.

Astronomers have done incredibly comprehensive surveys of the sky, and mapped out where the

blobs of dark matter are, and how they surround galaxy clusters.

One famous example of this is the Bullet Cluster, where astronomers could observe clusters of

galaxies colliding with each other.

They could see the stars in the galaxies, they could measure the locations of giant

clouds of hot gas colliding because of the X-rays they emit, and they could measure the

dark matter through its gravitational lensing.

And what they found was amazing.

The stars are so far apart, they just pass by one another without colliding.

The gas does collide, and bunched up into regions that glowed bright in X-rays.

But surprisingly, the dark matter didn't collide with anything, not with the gas, stars

or even itself.

If dark matter is a particle, it must be tiny - astronomers say it has a small cross section.

And yet, it has to be massive, since it dominates the area with its gravity.

Better observations across the large scale structure of the Universe show how dark matter

must have been necessary to get these galaxy clusters collapsing in the ways they do, and

the gravitational lensing observations are now so precise, they can see the exact distributions

that match these predictions.

Another survey of dark matter was to search for it in the Cosmic Microwave Background

Radiation, of course.

This is the afterglow from the Big Bang.

A time when the Universe was about 380,000 years old, and light was finally able to escape

into space.

The European Space Agency's Planck satellite performed an all sky survey of this cosmic

microwave background, mapping out the distribution of dark matter compared to regular matter

in the sky.

When you look at the CMB, the temperature fluctuations tell you how much regular matter

and energy there is compared to dark matter.

When that early Universe was so hot and dense, the radiation pushed against regular matter,

while it didn't push against the dark matter.

Astronomers have built models with different ratios of dark matter to regular matter, to

match up the one they see in the CMB.

Based on this survey, astronomers were able to calculate that the Universe is made of

4.9% regular matter and 26.8% dark matter.

Oh, and another 68.3% dark energy, but again, that'll have to be another episode.

Astronomers are certain that dark matter is there, but they still don't know what it

is.

As my friend Dr. Ethan Siegel says, "When someone puts forth the hypothesis that dark

matter doesn't exist, the onus is on them to answer the implicit question, okay then,

what replaces General Relativity as your theory of gravity to explain the entire Universe?"

What's your general theory of sound that replaces my idea that my car is making a strange

knocking noise?

Now, I hope, I've convinced you that astronomers aren't arrogant, they've got a genuine

mystery they're trying to chase down through observation and experiment.

And I'll get to them in a second, but first I'd like to thank:

Hadi Zolfaghaari Dany Noacco

Gaute Moon Incrediwebbs

Joseph Matheny Bruce Jividen

And the rest of our 837 patrons for their generous support.

If you love what we're doing and want to get in on the action, head over to patreon.com/universetoday.

In the last few decades, astronomers have continued to search for dark matter.

Narrowing down what it might be: invisible particles or gravity behaving strangely at

large distances.

When it comes to particles, there are three possibilities: hot, warm and cold.

In this case, hot dark matter would be a particle that's moving close to the speed of light,

while cold would indicate that it's moving very slowly.

An example of hot particles are neutrinos.

These are the nearly massless particles streaming from the Sun and other stars.

At any point you've got about 100 trillion of these tiny particles passing through your

body, moving at nearly the speed of light.

They rarely interact with anything out there in the Universe.

In fact, a neutrino will, on average, be able to fly through a light-year's worth of lead

without getting stopped.

Physicists detect neutrinos in enormous underground reservoirs of water surrounded by incredibly

sensitive detectors.

When the occasional neutrino does interact with a molecule of water, it releases a cascade

of particles which can be detected.

That sounds like a good candidate for hot dark matter, right?

Well, the problem is that neutrinos are moving close to the speed of light.

This means that won't ever clump up in the way that astronomers observe dark matter doing,

through gravitational lensing and the cosmic microwave background radiation.

Since dark matter doesn't seem to clump at all, hot, fast moving particles are ruled

out.

Sorry neutrinos.

Instead, slower moving, cold dark matter particles seem like the most likely culprit.

There are literally dozens of experiments searching for cold dark matter particles right

now.

They're all based on the idea that even if dark matter barely interacts with matter,

it can happen from time to time and you can observe it.

Experiments are running to detect every possible particle theorized.

Let me give you just one example: the Super Cryogenic Dark Matter Search, or SuperCDMS.

The experiment is located 700 meters underground in an old mine in Minnesota.

Assuming that dark matter is this cold, slow moving particle that comprises the vast majority

of matter in the Universe, and assuming that it doesn't really interact with regular

matter, you'd expect many of these particles to be passing through any spot on the Earth

at all times.

Every now and then, one of these dark matter particles would interact with regular matter

and release a cascade of particles that could be detected.

This old mine is deep underground, shielded away from cosmic rays and human pollution,

so only particles that can pass through hundreds of meters of rock will be detected.

It gives scientists a clean signal.

The detector is equipped with silicon and germanium crystals cooled down just above

absolute zero.

This is going to sound totally new age, so bear with me.

If dark matter particles pass through the detectors, they'll set off vibrations in

the crystals that will be detectable.

An even more sensitive version is under construction at a deeper facility in Sudbury, Canada.

Once it's fully operational in the 2020s, SuperCDMS SNOLAB will be able to detect cold

dark matter particles with a mass between 1 and 10 protons.

Another way scientists are searching for dark matter is using particle accelerators, like

the Large Hadron Collider.

Instead of waiting for dark matter particles to drift into their detectors, they've tried

to create them.

Particle accelerators work by pushing particles to immense speeds, creating an enormous amount

of kinetic energy.

When the particles are slammed into each other, that kinetic energy freezes out into matter,

which can then be studied.

Different models for dark matter have been proposed, and the right combination of energy

and particle collisions could generate a particle that matches the properties of dark matter.

Another experiment at CERN is called OSQAR, or the Optical Search for QED Vacuum Bifringence,

Axions and Photon Regeneration.

It's searching for particles known as axions, which could be a candidate for dark matter.

It involves firing a laser down a vacuum chamber which is exposed to an incredibly powerful

magnetic field.

As the photons travel down this chamber, some of them could turn into axions.

At the end of the chamber there's a barrier.

The visible light is blocked by the barrier, but the axions should be able to pass through

this wall and then turn into photons on the other side again.

At this point, there's no concrete evidence for axions, but there are several experiments

searching for them.

A much longer vacuum chamber is in the works, and there's a counterpart to OSQAR called

the CERN Axion Solar Telescope, which is looking for axions coming from the Sun.

There's a detector on board the International Space Station called the Alpha Magnetic Spectrometer

which could be the one to discover dark matter.

In its first 5 years of operation, the instrument detected over 90 billion cosmic ray events:

protons and other particles moving at close to the speed of light.

These particles contain vastly higher energy than anything that could be produced in the

Large Hadron Collider, so they're like a natural particle accelerator.

One indication for dark matter could be the hundreds of thousands of particles of antimatter

which have already been detected by the AMS.

The source of this antimatter is still a mystery, but one idea is that it's a side effect

from particles of dark matter occasionally colliding with itself.

Perhaps the most epic particle detector is the IceCube neutrino lab, located in Antarctica.

This giant telescope is a series of detectors embedded into a glacier - it's one cubic

kilometer of ice.

When neutrinos and other particles pass through a vast volume of water, they can occasionally

interact and release a cascade of particles.

IceCube has been one of the most important instruments for physicists, setting limits

on the mass of particles that dark matter could be.

At this point, scientists still don't know what dark matter is.

But with dozens of experiments, they're continuing to search, and better narrowing

down what it can't be.

At some point in the future, we can look back at this search with a definitive answer.

I really enjoy a mystery, and being a journalist gives me a chance to watch the search for

dark matter unfold, day after day, as ideas are tested, falsified, rejected, and replaced.

This is science.

This is how it works, and the journey is as important as the destination.

What do you think?

Let me know your thoughts in the comments.

Once a week I gather up all my space news into a single email newsletter and send it

out.

It's got pictures, brief highlights about the story, and links so you can find out more.

Go to universetoday.com/newsletter to sign up.

All of my videos are also available in handy audio and video podcast formats so you can

have our latest episodes show up right on your audio device.

Go to universetoday.com/audio or universetoday.com/video to get the one you want.

And I'll put the links in the shownotes.

And finally, here's a playlist.

For more infomation >> How Are We Searching For Dark Matter? And How Do We Even Know It's Real? - Duration: 16:02.

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6- His walk | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:39.

For more infomation >> 6- His walk | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:39.

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17- His sentimentality | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:39.

For more infomation >> 17- His sentimentality | responding to Wilders' #MuhammadCartoonContest | Fadel Soliman - Duration: 0:39.

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FORTNITE Tomato Challenge IRL - The NEW Ice bucket challenge - Duration: 5:30.

hey you what's going on guys it's Finn's

here wpg and we played games Network and

we're back with an amazing amazing

amazing video I hope you guys like it

it's the challenge Oh

challenges stick around you're gonna

find out more about it you gotta love it

you're gonna love it

hey guys welcome back all right now

you're probably wondering where robox

channel what do we got for tonight

up on the screen well you know I play

for tonight you know I love for tonight

you know I love watching for tonight

and this is a fortnight face challenge

and please guys stick around to the end

find out all information it's gonna be

amazing it's an amazing amazing

challenge within an amazing goal in mind

so let's go ahead and talk about it real

quick so this is for tonight as you can

see we got the praise the tomato and

moat up on the screen now what is it man

if you don't know what it is man you've

been living under a rocket this is the

praise the tomato ammo wait for it oh

poor dude poor dear poor dude

but guys so this challenge was brought

to us by mustard plays if you don't know

muster place and mustard man I don't

want to put too much information out

there but this dude is an amazing

family-friendly fortnight streamer kind

ID you know I don't want to throw too

much info out there but his brother is

actually the I believe the director of

creative operations for Epic Games which

is very cool very cool

and mustard love to play for tonight

family-friendly streaming and he brought

this challenge out today and I'm reading

this information off of Twitter here I

mean you probably read it already but

today I'm starting a new challenge for a

charity I'm calling it a boat night

tomato challenge and hoping we can help

raise money to fight cancer and have

some fun reenacting the praise the

tomato mote from 49 more details can be

found here I recommend you guys check

them out on Twitter

go to the link subscribe to his channel

this will take you directly to a video

on his channel and here's a little

preview of what we got to look forward

to

oh man I'm the face right in the face is

amazing bro who's amazing so there are a

little there's there's a little more to

the challenge so first off here's out

worst like he says you don't want to

pick a cancer charity to donate whatever

amount you can he did only $25 to the

American Cancer Society but he says

whatever amount you can and whatever

cancer charity is gonna work guys

secondly make a video of you doing the

praise of tomato mote from fortnight and

post the video to one or all of your

social medias and you know it's got to

get the word out right three challenge

at least five friends to do the

challenge to be sure to tag them in the

post oh I definitely will actually I'll

go ahead and call some people out right

now I wouldn't say that we are friends

but hey I know some guys out there

pretty big roblox youtubers that play

for tonight actually have some pretty

big 49 channels let's call them out

right now

Nick store very I know you're for

tonight channels been blowing up

recently bro love to see you do the

challenge rink your boss bro you want to

be a boss you got a fortnight channel

let's see what you got man there's a

couple other guys I know that would be

interested I'll let all these roblox

youtubers if you guys are interested

doing this man we'd love to see some

challenge videos I know a lot of you

play fortnight those are just two I'll

tag some more in my post now he has

challenged his brother Donald muster and

like I said that is the let's see what

he says

worldwide great of director of epic game

amazing he's also challenging some very

cool fortnight youtubers if you guys are

know I'm a seven sterling Upshaw stellar

will a bunch of other guys and Daryl

Eastern anyway guys without further ado

I know that I'm taking a lot of time

we're gonna go ahead and go right into

it

here's my fortnight tomato challenge

hope you guys enjoy

alright guys I hope you enjoyed the

video it was a good time for an amazing

cause

mustard plays bro you got great ideas if

you guys like I said if he doesn't know

mustard definitely go check him out I'm

gonna leave a link to his Twitter and

his YouTube channel down below as well

as I'm gonna leave a link to cancer or

Gore I mean there it is the American

Cancer Society webpage if you're

interested in donating

once again you can donate any amount I'd

love to see some video submissions broke

calling you Wow

you know who I'm talking about man I'm

calling you guys out get on in there and

get some video submissions if you guys

happen to be new to the channel man

what's up my name is Vince WB GN blue

the games Network

don't hesitate to subscribe smash that

like one if you liked the video and if

you guys would make sure and check out

these videos right over here thank you

guys have a wonderful day

peace

you

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