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Tackle that seemingly endless selection of course offerings; a roundup of helpful resources and sound advice for selecting the best courses and acing them.

What would happen if every human suddenly disappeared?
There are people everywhere. We live in the most remote regions of Earth's rainforests, oceans, and tundras, with settlements on every continent. Since we have had such a significant impact, the majority of scientists think that we have permanently altered Earth's geological history. So what would happen if everyone on Earth vanished overnight? Some of our inventions are so unmaintained that they quickly fail. Oil refineries break down, causing month-long fires at facilities like those in western India, the southern United States, and South Korea, hours after we vanish. Hundreds of drainage pumps in subterranean rail networks in cities like London, Moscow, and New York City are abandoned, filling the tunnels in just three days. The majority of backup generators will have stopped working by the end of the first week, and the earth will experience its first centuries-long blackout once the fires have been put out. Once the first disastrous month is through, things start to alter more gradually. The roots of trees and weeds have destroyed sidewalks in less than 20 years. Around this time, streets above flooded tunnels turn like urban rivers.The seasonal cycle freezes and thaws these streams in temperate areas, causing pavement and concrete foundations to break. In concrete structures, leaking pipes have the similar effect, and within 200 winters, the majority of skyscrapers will collapse. These structures eventually totally wash away in towns situated in river deltas, like Houston, flooding neighboring streams with smashed concrete. Rural and suburban regions deteriorate more gradually, but in ways that are generally expected. All of the typical adversaries of the homeowner—leaks, mold, bug and rodent infestations—now go unchallenged. The supporting beams of most houses have deteriorated and sagged within 75 years, and the fallen heap that resulted is now a haven for local rodents and reptiles.But "local" now has a new significance in this post-human world. Imported plants have taken over our cities and are now wreaking havoc on their new surroundings. Shanghai's rivers are covered in a lush green carpet of water hyacinth. The banks of London's Thames River are overrun by poisonous huge hogweeds. Streets in New York City are overrun with Chinese Ailanthus trees. Additionally, as concrete from submerged skyscrapers is added to the newly formed forest floor, the acidity of the soil decreases, possibly fostering the growth of new plant life. The animal kingdom is included in this post-human biodiversity. Animals explore new habitats with the aid of our abandoned bridges, following the unrestrained spread of native and non-native plants. In general, some creatures are saved by our infrastructure while others are doomed.In their native tropical settings, cockroaches continue to thrive, but without our heating systems, their urban relatives would probably freeze and go extinct in just two winters. Only a small number of resourceful pigs, dogs, and feral housecats are able to survive without us among the majority of domesticated animals. In contrast, the lessened light pollution saves more than a billion birds annually whose movements were hampered by high-tension wires and blinking communication tower lights. And one of their favorite artificial nurseries, rubber tires, which last for approximately a thousand years, is where mosquitoes never stop breeding. The Earth's temperature progressively recovers from millennia of human impact as wildlife and vegetation proliferate. The last traces of lead left in the soil by the Industrial Revolution are removed by the plant cycle after 35,000 years, and it could take another 65,000 years for CO2 to reach pre-human levels. But even millions of years later, humanity's legacy endures. America's Mount Rushmore, carved in unyielding granite, endures for 7.2 million years. Over 10 million people have been able to identify our bronze sculptures thanks to their chemical makeup. And the ruins of towns constructed on floodplains have been preserved in time as a kind of technological fossil by being buried far down. These remnants will eventually be removed from the planet's surface as well. Humanity hasn't always existed, and it won't always exist. But perhaps we can learn more about the world we currently live in by looking into the world without us.
By Niks3 years ago in Education
Why are some people left-handed
If you know an elderly left-handed individual, it's likely that they had to practice using their right hand to write or eat. Additionally, forcing kids to use their "proper" hand is still a prevalent practice in many parts of the world. Even the term meaning right, not only in English but in many other languages as well, also signifies correct or nice. But why does it happen in the first place if being left-handed is so wrong? Approximately 10% of people on the planet today are left-handed. It has remained that way for up to 500,000 years, according to archeological evidence, with 10% of human remains displaying the corresponding variations in arm length and bone density, as well as some ancient tools and artifacts displaying signs of left-hand use. And contrary to popular belief, being left-handed is not a decision. Based on the fetus' position in the womb, it can be predicted even before birth. Does that imply that handedness is genetic if it is inborn? Yes and no, I suppose. Despite sharing the same DNA, identical twins might have different dominant hands. In actuality, this occurs as frequently as it does with any other pair of siblings. But in remarkably regular ratios, your parents' handedness determines your likelihood of becoming right- or left-handed. You have a 17% probability of being born left-handed if your father is left-handed but your mother is right-handed, compared to a 10% chance for two righties to have a left-handed child. Although the chances are controlled by your DNA, handedness appears to be determined by a dice roll. All of this suggests that there is a reason why evolution developed and preserved this small percentage of left-leaning individuals over the course of millennia. Even while many hypotheses have attempted to explain why most individuals are right-handed or why handedness even exists in the first place, a recent mathematical model contends that the actual ratio indicates a balance between competing and cooperative influences on human evolution. The advantages of being left-handed are most obvious in situations when there is an adversary, such as in combat or competitive sports. For instance, over 50% of the best baseball hitters have been left-handed. Why? Consider it a pleasant surprise. Right-handed and left-handed athletes will encounter and train against righties the majority of the time because lefties are a minority to begin with. Therefore, when they face off, the left-hander will be more equipped to deal with this right-handed opponent, while the right-hander will be confused. This fighting theory is an example of negative frequency-dependent selection, where an imbalance in the population results in a benefit for left-handed fighters or sportsmen. However, groups that have a relative advantage typically continue to expand until that advantage vanishes, according to the laws of evolution. Natural selection would result in more lefties being the ones who made it if humans had just been battling and competing throughout the course of human development, until there were so many of them that they were no longer a rare advantage. Therefore, 50% of people would be left-handed in a society where competition is the only factor. But alongside competition, collaboration has also played a role in shaping human evolution. Additionally, cooperative pressure causes the distribution of hands to move the other way. Only 4% of the top golfers are left-handed, which is an example of the larger tool sharing phenomena in a sport where performance is independent of the competition. Many of the significant tools that have formed society were made for the right-handed majority, much as young people who might become golfers can more easily find a set of right-handed clubs. Lefties would be less successful in a world where everything was done cooperatively since they are worse at using these tools and have greater accident rates. Eventually, this would lead to their extinction. Therefore, the model shows that the persistence of lefties as a small but stable minority reflects an equilibrium that results from competitive and cooperative effects playing out simultaneously over time. This is demonstrated by accurately predicting the distribution of left-handed people in the general population as well as matching data from various sports. The information the data can give us about different populations is what is most fascinating. We may even discover that the solutions to some of the mysteries surrounding early human evolution are already at our fingertips, ranging from the skewed distribution of pawedness in cooperative animals to the somewhat higher proportion of lefties in competitive hunter-gatherer communities.
By Niks3 years ago in Education
At what moment are you dead
Humans have been captivated by death and resurrection for as long as we can remember. The dead keep returning, from our earliest mythologies to the most recent blockbuster movies, according to nearly every faith in the globe. But is it actually feasible to rise again? And anyhow, what actually distinguishes a dead corpse from a living one? We must first comprehend what life is in order to comprehend what death is. One old view was vitalism, which held that the reason why living things were exceptional was because they contained a unique component, or energy, which was the essence of life. Whether it was known as qi, lifeblood, or humors, there was a widespread belief in such an essence throughout the world. This idea is still present in tales of monsters who can somehow sap another person's life or of magical sources that may restore it. Following the Scientific Revolution in the 17th century, vitalism started to lose popularity in the Western world. René Descartes promoted the idea that a divinely created soul residing in the pineal gland of the brain gave life to the human body, which was fundamentally no different from any other machine. And in 1907, Dr. Duncan McDougall went so far as to assert that the soul had mass, weighing patients before and after death to support his assertion.There are still references to his thesis in popular culture despite the fact that his experiments, like the rest of vitalism, were disproved. Where do all these debunked hypotheses leave us, though? What we now understand is that life actually resides inside the active biological processes themselves, not in some mystical substance or spark. And we must enlarge our view to the level of our individual cells in order to comprehend these processes. Chemical events are ongoing inside each of these cells, fuelled by the glucose and oxygen that our bodies turn into ATP, a molecule that transports energy. For everything from repair to growth to reproduction, cells require this energy.The required molecules require a lot of energy to create, and even more energy to transport them to their final locations. Entropy is a universal phenomena that causes molecules to randomly diffuse, move from high concentration to low concentration, or even disintegrate into smaller molecules and atoms. Therefore, cells must constantly use energy to maintain their molecules in the extremely complex configurations required for biological functions to take place in order to keep entropy under control.Death ultimately follows from the breakdown of these arrangements when the entire cell is overcome by entropy. This is the reason why it is impossible to revive a creature that has already passed away. Air can be pumped into someone's lungs, but if the several other processes essential to the respiratory cycle aren't working, it won't be much use. Similar to this, the electric shock from a defibrillator resynchronizes the muscle cells in an abnormally beating heart so they resume their normal rhythm rather than jump-starting an inanimate object's heart. This can save someone from dying, but it cannot bring back a dead corpse or a monster made of dead bodies.It appears that despite all of our different medical wonders, death cannot be stopped or stopped from occurring. But that's not as easy as it might seem because ongoing medical and technological developments have led to diagnoses like coma, which describe potentially treatable situations for which people would previously have been regarded as dead. The line of no return might be stretched even further in the future. Some animals have been observed to lengthen their lifespans or endure harsh environments by practically pausing their basic processes. Cryonics research aims to accomplish the same by freezing the dead and resurrecting them when better technology is available. As you can see, when cells are frozen, diffusion all but ceases and there is very little molecular motion. A swarm of nanobots could theoretically turn back the clock on a person's cellular processes even if they had already stopped altogether. They could do this by repositioning every molecule in the body and simultaneously injecting ATP into every cell, causing the body to resume its normal functions. Therefore, death is just the result of growing entropy that upsets this delicate equilibrium if we consider life to be a state of immensely intricate, self-perpetuating organization rather than some mystical spark. And it turns out that the point at which someone passes away entirely depends only on how much of this entropy we are now able to reverse, rather than being a fixed constant.
By Niks3 years ago in Education
Why do your knuckles pop
What noise is that? The sound of popping joints can either be described as a sweet sense of relaxation or as the foul odor of an unpleasant habit, depending on who you ask. Honestly however. What noise is that? Why, specifically, do your joints snap like that when you bend them in a certain way? Numerous theories put up by scientists include quickly stretching ligaments and, in extreme situations, direct bone-on-bone contact.However, the most typical explanation for why your elongated joints make a popping noise is because, well, there are bubbles inside. The joints in your fingers are the most easily broken, but many people also break the joints in their hips, wrists, shoulders, and other joints in their neck and back. These are all synovial joints, which are your body's most flexible joints. A sticky fluid called synovial fluid, which includes lengthy, lubricating molecules like hyaluronic acid and lubricin, fills the space between the two bones. The main function of synovial fluid, which has a consistency similar to egg yolk, is to cushion the bones and make them more easily slide past one another. Additionally, it has phagocytic cells, which assist in clearing out any bone or cartilage fragments that wind up in the joint. However, it's crucial for knuckle cracking since, like other bodily fluids, it contains a significant amount of dissolved gas molecules. Knuckle-crackers are aware that in order to get that delightful pop, you must extend the joint beyond its natural range, for example by bending your fingers backwards. The bones separate from one another when you do it. Although the distance between bones widens, the volume of synovial fluid remains constant. Similar to how carbon dioxide bubbles out of soda when the cap is turned open, this results in a low-pressure zone that draws dissolved gases from the synovial fluid. The escaping gases create a bubble inside the joint, which pops. The bubble, however, bursts quickly. It is compressed by the liquids around it until it eventually falls. It can take a long before you can pop the same joint again since the bubble's gases disperse throughout the synovial cavity and gradually dissolve back into the fluid over the period of roughly twenty minutes. According to some scientists, there might be two pops. A bubble forms, and then a second bubble explodes. It may be because popping a joint causes it to momentarily widen that devoted neck, back, and knuckle crackers claim their joints feel more supple and flexible after engaging in the habit. But you could have heard that cracking your joints will cause you to develop arthritis from a worried family or a grumpy coworker. Donald Unger, a physician, also heard this. In an effort to disprove his mother's advice, he routinely cracked the knuckles on his left hand for 50 years while leaving the knuckles on his right hand unbroken. After 36,500 cracks, neither hand had arthritis. Dr. Unger was awarded an Ig Nobel Prize, a spoof of the Nobel Prize that honors bizarre yet oddly interesting scientific achievements, for his selfless act of devotion to science. According to Unger, his findings should compel further research into different parental perspectives, such as the significance of eating spinach. On that one, the verdict is yet out. One study on knuckle-cracking claims that all that joint bending and bubble popping can make your hands enlarge and make your grasp weaker. The biggest known risk, though, appears to be upsetting those around you.
By Niks3 years ago in Education
Exploring the Power and Evolution of the C Programming Language
Diving into the Depths of C Programming In the year 1972, a realm of boundless possibilities within the realm of computer programming was unveiled. This groundbreaking event transpired within the hallowed halls of renowned laboratories, where Dennis Ritchie conceived an innovation that would forever alter the course of programming history. The birth of the "C" programming language marked a pivotal moment that would shape the foundations of modern computing. Characterized by its modular structure and exceptional versatility, "C" emerged as a programming language of unparalleled significance. Its profound impact was soon to resonate throughout the technological landscape, and its legacy would become inextricably intertwined with the evolution of the Unix operating system.
By Ayshanasrin Aysha3 years ago in Education
Data Science Courses in Kolkata: Unveiling Trends, Factors, and Prospects
As the orchestration for adept data artisans escalates, Kolkata stands as a sanctum where the symphony of data science courses in Kolkata finds its crescendo. This dissertation embarks on an odyssey through the mystical factors that amplify this crescendo and the abundant avenues that beckon to the aspirants of data science courses in Kolkata.
By bizschoolkol3 years ago in Education
Smartphone Vision Syndrome
Introduction A. The rising prevalence of smartphones in modern society B. The detrimental consequences of excessive smartphone usage
By Naveed Ahmed Syed3 years ago in Education
Bangor University: Nurturing Minds, Shaping Futures
Introduction Welcome to an exploration of the prestigious Bangor University, a leading educational hub that has been shaping minds and fostering innovation for decades. Nestled in the breathtaking landscapes of Wales, Bangor University offers a diverse range of academic programs, cutting-edge research opportunities, and a vibrant campus life. In this comprehensive article, we'll delve into the myriad aspects that make Bangor University stand out in the realm of higher education.
By studyabroad3 years ago in Education
Crypto Quantum Leap
"Ready to kickstart your journey into the world of cryptocurrencies? Discover how you can dive into this exciting realm by clicking the link at the end of this article!"
By Drab3 years ago in Education
Exploring the Career Options for a Bachelor of Medical Laboratory Science
Medical laboratory science is essential to the healthcare industry since it is the basis for accurate disease diagnosis and treatment. Graduates with a Bachelor of Science (B.Sc.) in Medical Laboratory Sciences are qualified to work in clinical laboratories, research companies, and various healthcare settings. With this comprehensive degree's numerous professional opportunities, graduates can significantly impact patient care and public health. This article will review career options for people pursuing a BSc in Medical Laboratory Sciences.
By CGC 3 years ago in Education
Navigating Social Etiquette: A Guide to Building Meaningful Relationships
In a world defined by interconnectedness and communication, adhering to certain social rules can significantly enhance our interactions and relationships with others. These unwritten codes of conduct reflect our respect, empathy, and consideration for one another. Let's delve into some essential guidelines that can help us navigate the complexities of social interactions with grace and authenticity.
By Soumya Verma3 years ago in Education
How to Crack UPSC Exam on the First Attempt in 2023
At Dhyeya IAS Greater Noida, we stand as a pioneering IAS coaching institute in Greater Noida, dedicated to guiding and empowering UPSC aspirants to conquer the exam. With a proven record of success, our institute employs experienced faculty and strategic teaching methods to offer comprehensive courses covering all stages of the UPSC syllabus. Through regular mock tests, interactive sessions, and personalized mentorship, we ensure our students are well-prepared and confident to excel in the UPSC Exam, reflecting our commitment to their holistic development. Let us now dive deep into how to crack the UPSC Exam on the first attempt in 2023.
By DHYEYA IAS Greater Noida3 years ago in Education