Today I Learn

21 Sep 2023 17:16

The Little Death

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19 Sep 2023 07:12

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14 Sep 2023 02:58

​​What is the difference between Sugar Free, No Sugar Added, and Unsweetened?

Reading food labels can be tricky, especially when all the words sound like they mean the same thing. When you're grocery shopping and you see labels with "sugar free," "no sugar added," and "unsweetened," it may seem like you can buy any one of those products interchangeably. But each of those labels means something a little different.
The terms "sugar-free," "no sugar added," and "unsweetened" are often used on food and beverage labels to indicate different levels of sugar content or sweeteners. Here's an explanation of the differences between these terms:

Sugar-Free: "Sugar-free" means that the product contains no added sugars or sugar-based sweeteners. However, it's important to note that "sugar-free" doesn't necessarily mean the product is completely devoid of sweetness. Sugar alcohols or artificial sweeteners may be used as sugar substitutes to provide a sweet taste without adding actual sugar. It's crucial to check the ingredients list to see if any sweeteners or sugar substitutes are present.

No Sugar Added: "No sugar added" means that no additional sugars or sugar-based sweeteners have been added during the manufacturing process. However, the product may still contain naturally occurring sugars, such as those found in fruits or dairy products. It's important to read the nutrition facts label to determine the total sugar content and differentiate between naturally occurring sugars and added sugars.

Unsweetened: "Unsweetened" means that no sweeteners, including both natural and artificial sweeteners, have been added to the product. It indicates that the food or beverage is in its natural state without any added sweetness. However, it's essential to note that the product may still contain naturally occurring sugars, depending on the ingredients used.

When making dietary choices, it's important to consider individual dietary needs and preferences. If you're looking to reduce sugar intake, it's beneficial to read nutrition labels carefully and pay attention to the ingredients list to identify any hidden sugars or sweeteners that may be present. Additionally, it's advisable to consult a healthcare professional or registered dietitian for personalized guidance on sugar consumption and overall dietary choices.

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Today I Learn

10 Sep 2023 03:08

​​​​How does a Ball Point Pen work?

A Ball point pen is a pen that uses a small rotating ball made of brass, steel, or tungsten carbide to disperse ink as you write. All of the pens that preceded the ballpoint -- whether quill, metal or fountain -- used a watery, dark india ink that fed through the pen using capillary action. The ink can flow unevenly.
The ball is located in between the ink reservoir and the paper by a socket, and while it's in tight, it has enough room to roll around as you write. As the pen moves across the paper, the ball turns and gravity forces the ink down the reservoir and onto the ball where it is transferred onto the paper. It's this rolling mechanism that allows the ink to flow onto the top of the ball and roll onto the paper you're writing on, while at the same time sealing the ink from the air so it does not dry in the reservoir.

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07 Sep 2023 21:17

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05 Sep 2023 04:16

​​What is a Heart Murmur? What are some common reasons that Heart Murmurs occur?

Doctors listen to heart sounds by stethoscope. Normally heart sounds like "lub-dup". So there are two sounds : first heart sound (S1) and the second heart sound (S2). Sometimes a water flow like (whooshing or swishing) sound accompanies the "lub-dup". This is called heart murmur.

Heart murmurs are produced by turbulent blood flow across an abnormal heart valve, septal defect of heart or outflow obstruction from heart; or they may be produced by increased volume or velocity of blood flow through a normal heart valve.

Murmurs are produced both in normal and abnormal heart. Heart of pregnant woman and athletes may produce murmurs. These are the examples of "Innocent murmurs".

Other causes of heart murmur are : Valvular heart diseases (mitral stenosis and regurgitation, tricuspid stenosis and regurgitation, aortic stenosis and regurgitation, pulmonary stenosis and regurgitation), Patent ductus arteriosus, ventricular septal defect etc.

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31 Aug 2023 04:10

​​What is an Orthopaedic Shoe?

Orthopedic shoes, also known as custom-made therapeutic shoes, are designed for patients with significant deformities. They are made to fit specifically to their morphology. This equipment aims to improve the functions of walking, particularly thanks to the orthopedic insoles called plantar orthoses.

Orthopedic shoes feature orthotic insoles that provide good arch support. The main purpose of the arch support is to eliminate excessive pronation, which affects foot function and is the main cause of foot and heel pain.

Orthotic insoles help reduce pressure on the heel and the ball of the foot by transferring a substantial portion of body weight to the arch. In shoes without good arch support, the arch area doesn’t participate in distributing the pressure under the foot.

Excessive pronation causes the leg to internally rotate, putting stress on the knee, hip and lower back. Orthotic insoles with good arch support play an important role in alleviating stress on the knees, hips and lower back as well in improving foot and leg alignment.

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28 Aug 2023 03:45

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26 Aug 2023 07:08

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24 Aug 2023 19:44

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Today I Learn

20 Aug 2023 21:01

​​What Is The Metaverse?

The coining of the term “Metaverse” is credited to author Neal Stephenson from his science fiction novel “Snow Crash” in 1992. The novel envisioned the next internet iteration where lifelike virtual avatars connect with one another through virtual reality environments and realistic 3D buildings. Since then, technology advancements have enabled the beginning development of the metaverse with a combination of computers, wearable technology, and machinery, such as virtual reality headsets, augmented reality glasses, motion sensors, and game consoles where users are able to “live” within a digital universe.

Our current contemporary internet experience is two-dimensional where you scroll through and browse everything on a screen. The metaverse on the other hand is 3D, allowing you to “walk” through the two interwoven worlds via connected glasses or headsets that allow you to construct or participate in any universe you desire in the digital world.

In simple words "The Metaverse" is a collective, virtual, open space, created by the combination of virtually enhanced physical and digital reality. An example of an already existing Metaverse some would argue are platforms like Minecraft, Roblox or even fortnite which featured in-game concert featuring travis scott.

Imagine studying, working, interacting, attending concerts, earning money, and playing games in an online realm that is both an extension and a fusion of the real world. Besides, meetings with clients, digital entertainment, work training, and even online study are all expected to be available online in the future, thanks to the Metaverse. This is why so many businesses are investing in the Metaverse.

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14 Aug 2023 15:37

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08 Aug 2023 18:40

​​What Is A Vacuum Bomb And How Does It Work?

A thermobaric weapon, also called an aerosol bomb, a vacuum bomb or a fuel air explosive, is a type of explosive that uses oxygen from the surrounding air to generate a high-temperature explosion. The fuel–air explosive is one of the best-known types of thermobaric weapons. Thermobaric weapons are controversial because they are much more devastating than conventional explosives of similar size, and have a terrible impact on anyone caught in their blast radius.

This can be launched as a rocket or dropped as a bomb from aircraft. When it hits its target, the first explosive charge opens the container and widely scatters fuel mixture as a cloud. This cloud can penetrate any building openings or defences that are not totally sealed. A second charge then detonates the cloud, resulting in a huge fireball, a massive blast wave and a vacuum which sucks up all surrounding oxygen. The weapon can destroy reinforced buildings, equipment and kill or injure people.

They are used for a variety of purposes and come in a range of sizes - including weapons for use by individual soldiers such as grenades and hand-held rocket launchers.
Huge air-launched versions have also been designed, specifically to kill defenders in caves and tunnel complexes - the effects of this weapon are at their most severe in enclosed spaces.

Given their devastating impact, and their usefulness against defenders who are dug in to buildings or bunkers, thermobaric bombs have mainly been used in urban environments. There are no international laws specifically banning their use, but if a country uses them to target civilian populations in built-up areas, schools or hospitals, then it could be convicted of a war crime under the Hague Conventions of 1899 and 1907

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02 Aug 2023 04:51

​​How Do Hydrogen-Powered Cars Work?

Hydrogen is considered a fuel of the future. So how do hydrogen-powered cars work? Molecular hydrogen is a gas. As a chemical element, hydrogen is the most common element on Earth. And it contains a lot of chemical energy.

The fuel cell is a device that takes chemical energy, in the form of hydrogen, and turns it into electricity that can power an electric motor, just like a battery. So, a hydrogen-powered car is powered with an electric motor.

First, hydrogen stored in a tank (that is thick-walled and crash-tested, and usually under the rear seat) is mixed with air and pumped into the fuel cell. Inside the cell, a chemical reaction extracts electrons from the hydrogen.

The leftover hydrogen protons move across the cell and combine with oxygen from the air to produce water. Meanwhile the electrons create electricity, which charges a small storage battery used to power an electric drivetrain (just like in an electric vehicle).

This is why the vehicles are called Fuel Cell Electric Vehicles (FCEV), as compared to the battery electric vehicles (BEV) which are seen increasingly on our roads already.

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30 Jul 2023 02:44

​​What Were The Oscar Statuettes Made Of During World War II?

Officially named the Academy Award of Merit, the statuette is better known by its nickname, Oscar. Throughout most of Academy Award history, the Oscar statuettes have been crafted of solid bronze and plated in 24-karat gold.

Oscar statuettes are 13.5 inches tall and weigh eight-and-a-half pounds. That's a hefty little metal guy to be clutching when you're emotionally overwhelmed and being broadcast live around the world. But for three years during World War II, Academy Award winners bore a lighter load when they accepted their statuettes.

However, due to a metal shortage during World War II, Oscars were made of painted plaster for three years. Following the war, the Academy invited recipients to redeem the plaster figures for gold-plated versions. The design of the statuette depicts a knight standing on a reel of film, holding a sword.

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20 Sep 2023 04:10

​​What is Gesture Recognition Technology and How Does It Work?

As the name suggests, gesture recognition is designed to recognize the physical movements, or “gestures,” of humans. Waving your hand in a particular pattern in front of the device, for instance, may tell it to launch a specific app. Gesture recognition such as this is often found in smartphones and tablet computers. 
Gesture recognition is classified as a type of touchless user interface (TUI). Unlike a touchscreen device, TUI devices are controlled without touch. A voice-controlled smart speaker like Google Home and Amazon Alexa are prime examples of TUIs. By speaking commands, you can control these devices, all without relying on touch. However, gesture recognition is also a type of TUI, as it’s also controlled without the use of touch. With that said, many devices that support gesture recognition also support touchscreen.
While there are many different types of gesture recognition technology, they all work on the same basic principle of recognizing human movement as a form of input. The device features one or more sensors — or cameras — that monitors the user’s movement. When it detects a movement that corresponds with a command, it responds with the appropriate output. This may be unlocking the device, launching an app, changing the volume, etc.

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18 Sep 2023 06:19

​​What are the importance of Foundation in building construction?

A strong and well-designed foundation is essential for any building construction for several reasons:
Structural Integrity: The foundation serves as the base on which the entire building structure rests. A strong foundation helps to distribute the weight of the building evenly, providing stability and ensuring that the building remains standing during natural disasters or ground movements.
Stability: A sturdy foundation ensures that the building remains stable and level. This is particularly important in areas prone to earthquakes, floods, or landslides, where a weak foundation can cause the building to collapse or shift.
Prevents Settlement: A well-built foundation helps to prevent settlement or sinking of the building, which can lead to structural damage or cracks in the walls and foundation.
Longevity: A good foundation can help to extend the lifespan of the building, preventing premature decay, and reducing the need for costly repairs.
Building Code Compliance: Building codes require that all buildings have a foundation that meets specific criteria. A properly designed and constructed foundation ensures that the building meets these requirements, ensuring compliance with the code.
A foundation is crucial in building construction as it provides structural integrity, stability, prevents settlement, increases longevity, and ensures building code compliance.

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10 Sep 2023 17:24

​​What Is Glare?

When a bundle of light hits a flat surface, it becomes polarized, or is reflected horizontally.  The bundle becomes concentrated and is blinding anyone observing it. This is referred to as blinding glare.

These reflections can be uniform, which is light reflected from a smooth service. Uniform reflections would be light reflected off the road, or off a car’s bumper or back window. They can also be non-uniform, which is light reflected from an uneven surface. An example of this would be light reflected off running water or a patch of ice on the road.

No matter what the case, the desired result is to filter out the distracting reflected light and provide a clear viewing experience for the wearer.

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07 Sep 2023 23:29

​​What is the function of Earwax in the Human Body?

The earwax is very useful substance which keeps our ears healthy and is produced naturally in the ear. This wax is found not only in humans, but also in animals. It cleans, protects and lubricates the ears. Let us study through this article about earwax, its function etc.

The scientific name of the earwax is cerumen. It is formed in the outer part of our ear canal where there are thousands of glands. It is sticky and shiny substance. It coats the ear to moisturize it and fight against infection. Earwax also prevents from dust, dirt, and insects from entering the ear.

It also works like a natural antibiotic, i.e. it contains anti-microbial properties. According to some researchers, cerumen contains a lysozyme antibacterial enzyme which is capable of destroying the walls of the cells of bacteria.

With the help of earwax, you can tell which family you belong to. People have wet or dry wax. Although, both the wax is made up of chemicals. But it depends upon the family that the wax will be wet or dry in your ear. This is detected by the gene. This gene is called ABCC11. If the gene G is replaced by gene A, then, the wax in the ear will be dry and its odour will also be different.

Earwax works by: Protecting and moisturizing the ear canal skin, Preventing dry & itchy ears, Utilising special chemicals that help ward off ear infections. Shielding the eardrum. Trapping dust, dirt, water and other things that can enter your ear, so they don’t travel any further. Earwax is essential to good ear health. However, build-up can easily be problematic for your overall quality of hearing.

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06 Sep 2023 04:37

​​How does Digital Thermometer Work?

Digital Thermometers are slowly replacing the conventional mercury thermometer due to the ease of taking reading. People often have the misconception that it contains mercury. Digital Thermometers are mercury free. These thermometers contain thermistor inside the tip which is used to measure the temperature. They provide quick and highly accurate results over the body temperature range.

These thermometers are easy to read with LCD display on them. They are equipped with beep alarm & memory function and can record a wide range of temperature. Doctor’s thermometer which are mostly used can read temperature between 94oF and 105oF (35oC and 42oC). It is three in one thermometer as it can record oral, auxiliary and rectal temperatures.

The tip is said as the heart of the thermometer. It is the placed closed to the body part to measure the temperature of the body. The tip of the Thermometer contains thermistor to measure temperature. It is a ceramic semiconductor which is bonded in the tip with temperature sensitive epoxy. It is covered with a cap so to prevent it from the outer world. The cap may be made up of metal or stainless steel. Thermistor is responsible for converting the physical temperature into electrical signals.

Thermistor is a special kind of semiconductor in which the value of resistance changes with the change in temperature. Due to change in resistance value, the output voltage changes and the temperature change is detected.

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03 Sep 2023 05:37

​​What purpose do Reflectors serve in Photography?

A Reflector refers distinctly to an equipment used by photographers and cinematographers to bounce light in a certain direction. It acts as a medium to bounce light and redirect light to illuminate the subject more effectively! A reflector can be either artificial or natural, natural reflectors are objects in the environment that naturally reflect light - cars, walls, buildings, roads and other reflective surfaces are natural reflectors.

Artificial reflectors are used by photographers to control the brightness and intensity of available light and to counteract harsh over exposure due to available light. The artificial reflector is made up of two parts, the reflective material and the frame. The purpose of the frame is to keep the reflective material taught at an angle that directs the reflected light to a specific direction.

There are many different reflective surfaces used, the most common being, white, silver and gold. Depending on the specific reflective material used, a different effect is achieved by varying the distance from the subject and angle of reflected light. Black colored reflectors are used to absorb light and introduce shadows.

Reflectors empower the photographer to control the quality of light and also gives them control over the overall contrast and shadows created by reflecting natural or artificial light from a light source. An additional use of reflectors is when it is coupled with a studio strobe. it varies the angle at which the light is emitted out. Reflectors vary in size and shape and depending on the particular need of the photographer or cinematographer to light a scene, a particular type of reflector is used.

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28 Aug 2023 07:16

​​What’s the difference between Optical Zoom and Digital Zoom?

Zoom is a term that is often used in photography which signifies a change in the apparent distance between the camera and the subject.

Zooming in photography is generally of two main types optical zoom and digital zoom. Both the methods use different technologies and produce different qualities in the results.

The main difference between optical zoom and digital zoom is that optical zoom involves a physical camera lens movement, which changes the apparent closeness of the image by altering its focal length whereas in digital zoom, the pixels are enlarged at the center of the screen and the scene being clicked is magnified.

Optical zoom is caused by the physical movement of the lens of the camera. It helps to magnify the scene without affecting the quality of the photo.

Optical zoom provides clearer and zoomed photos.

Optical zoom works by altering the focal length of the lens, thus bringing the image closer.

On the other hand, digital zoom is a type of inbuilt processing software in the camera that the user can use to zoom in after the picture has been clicked.

It is done by enlarging the pixels in the center of the screen therefore it causes a decrease in the quality of the image and less resolution.

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26 Aug 2023 17:05

​​What Is Difference Between Whey Protein And Whey Isolate?

When searching for protein powders, you may have encountered the whey protein vs whey isolate debate. Whether you're looking to build muscle or you’re after the best protein powder for weight loss, you'll come across these two whey-based proteins a lot. Both come from dairy; whey is a byproduct of cheese production. But there are several differences between the two.

Whey isolate is just whey protein but with the lactose, a sugar commonly found in dairy, removed. As a result, whey isolate tends to have a lower fat and calorie content and a higher protein intake per serving than whey protein, which has a higher calorie and fat content due to the lack of additional processing.

Whey isolate tends to have a slightly higher protein content than simple whey protein powder, as the process which removes the lactose from the powder also concentrates the protein somewhat.

Whey isolate tends to have a lower calorie, carbohydrate and fat count, which makes isolate ideal for mixing with water for a low-calorie, high-protein drink. Great for building lean muscle. Whey protein is still a very efficient way to cram more protein into your diet, whether you’re making shakes or pouring scoops of the stuff into pancake mix, oats or your morning yoghurt. However, it does come loaded with a few extra calories.  

If you’re just after a drink to add more protein to your diet without additional calories, fat or triggering any digestive issues with lactose you may have, whey isolate is what you’re after. However, whey protein, as a more common supplement, is often seen on offer and at far greater varieties of flavour.

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25 Aug 2023 18:22

​​What Is Negative Ion Technology?

Negative ion technology embeds negative ions in personal products and is currently being advertised as a means to maintain health, balance energy, and improve well-being. This technology is used in certain silicone wristbands, quantum or scalar-energy pendants, and kinesthesiology tape.

Negative ions are also made when sunlight, radiation, air, or water break down oxygen. The minerals that produce these negative ions often include naturally occurring radioactive substances such as uranium and thorium.

It is believed that negative ions create positive vibes and uplift the mood. They show the various mental and physical health benefits, such as stress reduction, better sleeping, respiration etc. whereas these ions may also act on pollutants, make them negatively charged and get them collected on surfaces.

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23 Aug 2023 19:02

​​What Is A Car Brain Box?

A Car Brain Box is an electronic device that incorporates micro processors for controlling multiple functions in a vehicle, such as cruise control, automatic gear shift, climate control, engine running, emission control, fuel injection, collision avoidance, Powered mirror, seat & rear mirror controls etc. 

The Brain Box is also known as the PCM (Power-train Control Module), ECM (Engine Control Module) or the ECU (Engine Control Unit). A brain box is usually much more complex than this, doing lots of complex calculations and taking complicated decisions to run the vehicle maximally.

Before manufacturers switched to using engine control modules and a large network of computers to control the vehicles functions, everything was manual. Typically the only non-mechanical item in an older vehicle was the radio. Windows, door locks, and all the basic functions drivers now expect in their vehicles were manually operated.

One of the primary functions of an ECU is monitoring a series of a cars actions to register errors with how it is operating. If an error is detected the ECU will generate a trouble code. Once the ECU notices the problem and generates the trouble code, it will cause the check engine light to come on. So if you ever think of your engine as the heart of your vehicle system, then you should consider the Brain Box as the Brain.

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18 Aug 2023 04:49

​​What Is The Great Green Wall?

The Great Green Wall is an African-led movement with an epic ambition to grow an 8,000km natural wonder of the world across the entire width of Africa.  A decade in and roughly 15% underway, the initiative is already bringing life back to Africa’s degraded landscapes at an unprecedented scale, providing food security, jobs and a reason to stay for the millions who live along its path. 

The Wall promises to be a compelling solution to the many urgent threats not only facing the African Continent, but the global community as a whole, notably climate change, drought, famine, conflict and migration. Once complete, the Great Green Wall will be the largest living structure on the planet, 3 times the size of the Great Barrier Reef.

The Great Green Wall isn’t just for the Sahel. It is a global symbol for humanity overcoming its biggest threat – our rapidly degrading environment. It shows that if we can work with nature, even in challenging places like the Sahel, we can overcome adversity, and build a better world for generations to come.

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10 Aug 2023 06:36

​​What Is The Difference Between Map And Globe?

A map and a globe are very much different. While a map gives a two dimensional presentation of certain regions in the world, a globe gives a three dimensional presentation of the entire world. A map is easy to use and portable, whereas a globe is not. The regions can be easily identified in a map than in a globe.

A map presents the physical features of a particular region of the earth on a plane surface. Maps come with various symbols and signs related to the geographical and physical features. A globe can be called as a duplicate earth. It is round in shape and shows accurate areas, distances, directions and relative shape and size.

A map presents a distorted view as it is flat. On the contrary, a globe presents a less deformed view as it is round in shape. When talking of accuracy, a globe is more accurate than the map. Maps may have wide gaps between regions, that are not seen in globes that only give the right measurements. In a map, one can see that the land towards the North Pole is shown larger than they are. It can also be seen that Antarctica is stretched shown as a stretched continent when it is actually round.

If a person is looking for more details, the map is the best one as it features a lot about specific regions. A map may include the boundaries, rail routes, climatic conditions, latitudes, longitudes and a lot more. Moreover, there are also various types of maps like geographical, physical, weather, tourism and transportation maps to name a few. Globe does not have all these minute details and also does not have many variations.

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05 Aug 2023 03:34

​​What Is Polycystic Ovarian Syndrome?

Polycystic ovarian syndrome (PCOS) is a hormonal imbalance caused by the ovaries (the organ that produces and releases eggs) creating excess male hormones. If you have PCOS, your ovaries produce unusually high levels of hormones called androgens. This causes your reproductive hormones to become imbalanced.

As a result, people with PCOS often have erratic menstrual cycles, missed periods and unpredictable ovulation. Small cysts may develop on your ovaries (fluid-filled sacs) due to lack of ovulation (anovulation). However, despite the name "polycystic," you do not need to have cysts on your ovaries to have PCOS.

PCOS is one of the most common causes of female infertility. It can also increase your risk for other health conditions. Your healthcare provider can treat PCOS based on your symptoms and if you have plans for having children.

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01 Aug 2023 04:33

​​What Was The First Animal To Orbit The Earth?

In the 1940s and 1950s, the Soviet Union and US space programmes sent numerous species of animals into space, including monkeys, mice and dogs. However, these were suborbital flights, which meant the spacecraft passed into outer space before falling back to Earth without making an orbit.
 
The first animal to make an orbital spaceflight around the Earth was the dog Laika, aboard the Soviet spacecraft Sputnik 2 on 3 November 1957. Laika and two other dogs (Albina and Mushka) were placed in increasingly smaller cages over several weeks. With her calm temperament and grace under pressure, Laika was chosen. Vladimir Yazdovsky, the leader of the Soviet space mission, described Laika as “quiet and charming.”

Laika’s spacecraft, Sputnik 2 was fitted with a variety of innovative devices to keep her alive. There was an oxygen generator which absorbed carbon dioxide, a heat-activated fan to regulate the temperature and the capsule was stocked with enough food to keep the dog alive for seven days. 

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27 Jul 2023 05:16

​​What Do We Actually Smell When It Rains?

When those first fat drops of summer rain fall to the hot, dry ground, have you ever noticed a distinctive odor? Of course rain itself has no scent. But moments before a rain event, an “earthy” smell known as petrichor does permeate the air. People call it musky, fresh, generally pleasant.

Petrichor is the term coined by Australian scientists in 1964 to describe the unique, earthy smell associated with rain. It is caused by the water from the rain, along with certain compounds like ozone, geosmin, and plant oils.

Petrichor is a combination of fragrant chemical compounds. Some are from oils made by plants. The main contributor to petrichor are actinobacteria. These tiny microorganisms can be found in rural and urban areas as well as in marine environments. They decompose dead or decaying organic matter into simple chemical compounds which can then become nutrients for developing plants and other organisms.

A byproduct of their activity is an organic compound called geosmin which contributes to the petrichor scent. Geosmin is a type of alcohol, like rubbing alcohol. Alcohol molecules tend to have a strong scent, but the complex chemical structure of geosmin makes it especially noticeable to people even at extremely low levels. Our noses can detect just a few parts of geosmin per trillion of air molecules.

When raindrops fall on the ground, especially porous surfaces such as loose soil or rough concrete, they will splatter and eject tiny particles called aerosols. The geosmin and other petrichor compounds that may be present on the ground or dissolved within the raindrop are released in aerosol form and carried by the wind to surrounding areas. If the rainfall is heavy enough, the petrichor scent can travel rapidly downwind and alert people that rain is soon on the way.