Today I Learn

2021-05-29 04:23:57 Open / Comment

2021-05-28 07:53:06 Do blind people dream in visual images?

Yes, blind people do indeed dream in visual images. For people who were born with eyesight and then later went blind, it is not surprising that they experience visual sensations while dreaming.

Dreams are drawn from memories that are stored in the brain as well as from brain circuitry that is developed while experiencing the outside world.

Therefore, even though a person who lost his vision may be currently blind, his brain is still able to draw on the visual memories and on the related brain circuits that were formed before he went blind.

For this reason, he can dream in visual images.

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2021-05-27 05:08:33 ​​How do vaccines work?

Vaccines contain weakened or inactive parts of a particular organism (antigen) that triggers an immune response within the body. Newer vaccines contain the blueprint for producing antigens rather than the antigen itself. Regardless of whether the vaccine is made up of the antigen itself or the blueprint so that the body will produce the antigen, this weakened version will not cause the disease in the person receiving the vaccine, but it will prompt their immune system to respond much as it would have on its first reaction to the actual pathogen.

Some vaccines require multiple doses, given weeks or months apart. This is sometimes needed to allow for the production of long-lived antibodies and development of memory cells. In this way, the body is trained to fight the specific disease-causing organism, building up memory of the pathogen so as to rapidly fight it if and when exposed in the future.

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2021-05-25 04:14:54 ​​How does Robot Vacuums work?

Most robot vacuums consist of one or two spinning brushes and a rolling brush or two.

These work in conjunction to bring large and small debris inwards to the center, where the vacuum mechanism sucks it up into the waste bin of the device. Dirt, fur, food, hair, and everything else the vacuum collects gets stored in a removable section.

Once this is filled, the owner will typically have to remove the tray and dump everything into the trash.

The best autonomous robot vacuums also include various types of sensors.

Downward-facing sensors are the most common and help the device from driving over a ledge such as stairs.

More expensive models have sensors on top that can map rooms as they clean. Basic robot vacuums can be programmed to run on a schedule using controls on the device itself.

Higher-end models can be managed by basic controllers as well as smartphone apps or even a smart speaker.

No matter which device you end up owning, you can be sure that it will pick up debris from all over your residence.

As these vacuums can be programmed to run when you are not home, you can come back to a clean house every day of the week.

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2021-05-25 04:14:49 Open / Comment

2021-05-23 07:23:35 ​​What is firmware?

Firmware is a small piece of software that makes hardware work as its manufacturer intended it to.

It consists of programs written by software developers to make hardware devices "tick." Without firmware, most of the electronic devices we use daily wouldn't be able to work.

They would not do anything.

For example, did you know that a simple traffic light has firmware on it?

Yes, it does, and the firmware is what tells it to change the lights at regular intervals.

Without firmware, the traffic light would be just a "stupid" mast, placed on the side of the road, doing nothing except looking bored.

What is firmware in the case of less sophisticated hardware devices such as traffic lights, washing machines, card machines, surveillance cameras, and TVs?

The firmware is all the software on them, also acting as their operating system and controlling everything about those devices’ functioning.

Traffic lights need firmware to run.

We often tend to think about a hardware device as a device that is just hardware. And we assume that it just works by itself. However, almost none of the modern hardware devices would work without this particular software written directly onto them.

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2021-05-23 07:23:33 Open / Comment

2021-05-16 09:42:06 Open / Comment

2021-05-16 09:42:01 ​​Why do some people feel sick if they read in a moving vehicle?

Motion sickness in general is caused when your inner ear and your eyes disagree about whether you’re moving. When you read in a car, your visual field stays still but your inner ear detects the twists and turns. This sensory conflict triggers nausea, possibly because the brain thinks you’ve eaten something toxic that’s making you hallucinate. Motion sickness occurs when the three parts of our body that sense movement the eyes, inner ear, and sensory nerves send different signals to the brain.

Here's how these three systems sense movement and balance: Your eyes allow you to see that you're moving, the nerves in the muscles and joints of your extremities allow you to feel that you're moving, and the inner ear has canals with fluid that moves around and this allows the body to perceive motion. All of these send the sensory information to your brain, which then tells you that you are moving.

Motion sickness typically occurs when only one or two of those centers (usually the inner ear) sense you are moving, and the other(s) do not so there's a mismatch in communication to the brain. Your brain gets confused because it's getting mixed signals and sensing this abnormal movement, which results in nausea or vomiting.

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2021-05-10 06:36:00 ​​What is Muscle Fatigue?

At the start of exercising or when performing tasks, your muscles feel strong and resilient. However, over time and after repeating movements, your muscles may begin to feel weaker and tired. This can be defined as muscle fatigue.

Muscle fatigue is a symptom that decreases your muscles’ ability to perform over time. It can be associated with a state of exhaustion, often following strenuous activity or exercise. When you experience fatigue, the force behind your muscles’ movements decrease, causing you to feel weaker. Exercise and other physical activity are a common cause of muscle fatigue. Other possible causes of this symptom include: Addison’s disease age, anemia, anxiety, cerebral palsy, chronic fatigue syndrome (CFS), dehydration, depression, hepatitis C, HIV, influenza (the flu), lack of exercise, lactic acid production, medications, mineral deficiency, muscular dystrophy, myositis (muscle inflammation), poor muscle tone due to a medical condition, pregnancy, sleep deprivation, stroke, etc.

Muscle fatigue can occur anywhere on the body. An initial sign of this condition is muscle weakness. Other symptoms associated with muscle fatigue include: soreness, localized pain, shortness of breath, muscle twitching, trembling, a weak grip, muscle cramps. If you begin having difficulty performing daily tasks or if your symptoms worsen, seek immediate medical attention. This could be an indication of a more serious health condition.

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