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  • It's AumSum Time.

  • Can you guess the title of my next video?

  • Hurry up.

  • Write your guess in the comments section below.

  • What is depression?

  • It is a 5 star hotel deep underwater.

  • As usual.

  • You are wrong.

  • In our life, all of us feel sad or depressed for some time.

  • But that doesn't mean we have depression.

  • Many doctors use a manual named Diagnostic and Statistical Manual of Mental Disorders to diagnose depression.

  • It has a list of symptoms which include sadness, worthlessness, hopelessness, changes in appetite, suicidal thoughts, sleep problems, etc.

  • If we have five or more of these symptoms for at least two weeks, then doctors diagnose us with depression.

  • The exact causes of depression are unknown.

  • But studies suggest that people who have depression may have a smaller hippocampus.

  • An area of the brain that regulates emotions.

  • Moreover, genetics might also play a role.

  • Studies have shown that a variation in the serotonin transporter gene makes us more prone to depression.

  • Environmental factors such as coping with the death of our beloved ones, traumatic events, etc. can also cause depression.

  • Topic: Buoyancy.

  • Can you drown in the dead sea?

  • Your answer must be yes, right?

  • You must be thinking that anybody who cannot swim will obviously drown.

  • Whether it is a swimming pool or the dead sea.

  • However, that is not 100% true.

  • Confused?

  • Let me explain to you.

  • When an object is partly or wholly immersed in a fluid, an upward force is exerted by the fluid on that object.

  • This tendency of the fluid to exert an upward force on the object is called buoyancy or upthrust.

  • This upward force is called buoyant force.

  • So, do you finally get it?

  • Let me give you one more example.

  • Place a piece of wood in water and push it downwards.

  • What do you observe?

  • It seems like something is pushing the piece of wood upwards, right?

  • Water exerts an upward force on the wood.

  • That is why the wood is getting pushed upwards.

  • This force is called buoyant force and the tendency of water to exert that buoyant force is called buoyancy.

  • Dead sea has a huge amount of salt dissolved in it as compared to any other sea or ocean.

  • The presence of this salt increases density of water present in the dead sea.

  • Higher density leads to greater buoyant force.

  • As the dead sea has very high density, it exerts enough amount of buoyant force to make us float on it.

  • So, if we can float on the dead sea, we are definitely not going to drown in it.

  • Topic: Latent heat of vaporization.

  • Why does steam cause more severe burns than boiling water?

  • It is because steam is jealous of boiling water.

  • No.

  • It is because of latent heat of vaporization.

  • Latent heat of vaporization is the amount of heat energy required to change a unit mass of liquid into vapor at atmospheric pressure at its boiling point.

  • Trust me.

  • Everthing just went over my head.

  • Alright.

  • I'll explain it to you.

  • Boiling water contains only a specific amount of heat energy required for it to boil.

  • However, as steam is formed from boiling water.

  • It contains the heat energy of boiling water, along with the latent heat of vaporization.

  • Hence, as steam has more heat energy, it can cause more severe burns than boiling water.

  • Why do your eyes turn red in the pool?

  • It is because of chlorine.

  • Chlorine is not the main reason for this.

  • Chlorine is added to water of swimming pools because it is a disinfectant.

  • It helps kill germs, thus keeping water germ-free.

  • In fact, the main reason for our eyes to turn red is the presence of our bodily fluids like urine and sweat in the pool.

  • Urine and sweat contain nitrogenous compounds like urea.

  • Urea reacts with chlorine present in water, forming chloramines.

  • Now, if we regularly clean the swimming pools, then we can prevent the production of chloramines.

  • But if the pools are not cleaned, then the chloramines formed can irritate our eyes, thus making them red.

  • In addition to this, chloramines can evaporate from water.

  • Inhaling these chloramines for a long period can result in coughing, asthma and other health problems.

  • What is a stroke?

  • It is a new style of haircut.

  • No.

  • Through a complex system of arteries, our brain gets a continuous supply of oxygen and nutrients with the help of blood.

  • The cells of our brain alone use more than 20% of oxygen in our blood.

  • Hence, if the blood doesn't reach the brain cells, they can begin to die, thus giving us a stroke.

  • The most common stroke is Ischemic stroke.

  • Ischemic strokes occur when the arteries supplying blood to the brain get blocked.

  • Like the roads get blocked in a traffic jam, right?

  • Indeed.

  • Due to bad lifestyle choices and stress, fats and cholesterol gradually start building up in the arteries.

  • Thus, narrow them.

  • If this build up ruptures, a clot may form blocking the complete artery.

  • As a result, the brain cells begin to die due to lack of oxygen and nutrients.

  • Thus, giving an Ischemic stroke.

It's AumSum Time.

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什麼是抑鬱症?| 抑鬱症是什麼? (What is Depression? | #aumsum)

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    AumSum 發佈於 2021 年 01 月 14 日
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