Photography is much more complex than taking photos on a camera. Photography in its most basic definition dates back to ancient China, where the use of a camera obscura was first documented by a Chinese philosopher in the fifth century B.C. A camera obscura is the phenomenon where a small pinhole on a wall of a dark room allows light to come in. On the wall opposite to the pinhole, an upside-down image of the outside is illuminated. The science behind this strange phenomenon lies in the basic principles of optics, the study of light. Light travels in straight lines until it is blocked by a material, in which case the angle of the light changes. This concept of capturing light and forming an image was studied for hundreds of years, leading to the invention of microscopes to look at tiny living organisms, telescopes to look at the stars, and cameras to take pictures.
In this quick easy-to-understand lesson, we learn about atrial fibrillation, causes, symptoms, diagnoses, and treatments for USMLE medicine. Atrial fibrillation is the most common type of cardiac arrhythmia. This means the heart beat has an irregularly irregular rhythm. Symptoms can include fatigue, dyspnea (difficulty breathing), and heart palpitations in the chest. You diagnose atrial fibrillation via EKG. It can be treated with medications or surgically.
Water quenches thirst, is crucial when taking a bath, and is important when cooking. Yet despite the fact that it is all around us and used in our daily lives, there are many facts and health benefits about water that remain unknown to many people.
Crowds are often overlooked as a segment of psychology. Most people would like to say that they are independent and trail away from what others do, however, much goes unnoticed when talking about the human behaviour of an individual when placed in a large mass of others. This type of psychology becomes a unique aspect of how one may think purely based off of the interests and situation of a crowd. There are several theories and the concept itself plays a large role in several real-world situations with effective consequences.
The United Nations Educational, Scientific, and Cultural Organization (UNESCO) has several branches and initiatives aimed at promoting the subjects in its name across the globe. One of these is the World Heritage Committee which, among other things, decides what locations are worth preserving for various reasons. These reasons are grouped together in a list of ten selection criteria, each denoted by a Roman numeral. To explain the Committee’s selection criteria and World Heritage sites more broadly let us go through this list and examine an illustrative example for every criterion.
Petroleum (or oil) and natural gas are widely used sources of fuel. Around the world many transportation, energy, and heating infrastructures depend in large part on one or both of these hydrocarbon-rich fuels, petrochemical products. While in the past it may have seemed inconceivable that people would have to step away from fossil fuels, climate change increasingly necessitates greener alternatives. It is also hard to imagine life without plastics. For many applications, such as in healthcare, there may be no better materials. A future with zero plastic is neither warranted nor desirable, but the threats to various ecosystems are likely to force the development of greener and more sustainable materials.
The earliest recorded instance of heeled shoes comes from tenth century Persia. Mounted soldiers wore shoes with heels to make it easier to keep their feet in their stirrups, as the heels would catch the back of the stirrup’s tread and stop their feet from sliding in and out. This same use can be seen to this day with cowboys and other jobs that involve riding horses. During this period heels went from being a masculine sign of strength and wealth to a non-gendered court fashion to a feminine fashion statement.
Innate vs Adaptive Immunity: What are the differences between innate and adaptive immunity? The human body has two protective immunological systems against pathogens: the innate immunity and the adaptive immunity. In this quick and easy lesson, we will explain the differences between the innate and adaptive immunity. The innate immunity and adaptive immunity differ based on the type of components that are used to protect the human body. For example, the innate immunity consists of neutrophils, dendritic cells, natural killer cells, macrophages, complements, physical barriers. On the other hand, the adaptive immunity contains components such as T cells, B cells, and antibodies to protect us from viruses, bacteria, and other pathogens.
When discussing space art, one can mean at least two different things. The term can refer to art made on Earth that is then sent into outer space, or art produced while in space. Going with the former definition, our exhibits come down to Earth’s closest neighbor in the Solar System and the rest of the cosmos.
The Top Ten Best Apps for Learning a Language: What better way to spend some free time during quarantine than by learning a language? Learning a language is scientifically proven to lower your chances of dementia and Alzheimers, increase your intelligence, and improve your concentration. It also opens up your range of outreach and communication to a much wider, more global scale, making the skill very appealing to employers and job-seekers alike. In this article, we will list the top ten best smartphone applications to utilize in your language learning endeavors, as well as list the languages that they offer.
The heart’s function is to consistently move the blood in the body for the blood to spread nutrients to other body parts or to be replenished with oxygen and nutrients from other respective organs. The heartbeat is a way to understand the pace at which the blood is moving and how quick the heart is pumping itself. A heartbeat changes based on its environment. Running and high-intensity movement causes the heart to increase its number of beats whereas resting may lead to a lower heartbeat for the low amount activity that does not require as much oxygen. Depending on the difficulty and intensity of each activity, the heart accommodates via changing its pace to fit the body’s needs. In certain cases, however, a cardiac arrhythmia occurs and can lead to different cardiac issues that may or may not be harmless. Cardiac arrhythmia has affected millions of people in a multitude of forms. This article explains the basics of this condition such as heart block and bradycardia. The article is solely for educational purposes and not to diagnosis. What is a Cardiac Arrhythmia?
Cougar. Mountain Lion. Puma. What do these animals all have in common? Believe it or not, they are actually all names for the same animal! Because this feline spans such a large area, different areas call it different names. As you might think, this could get confusing if scientists try to discuss the same animal, so what do they do? They use taxonomy.
Taxonomy is the science and process of organizing organisms into categories and naming them. Every species of animal has a unique taxonomic, or scientific, name. A species is a group of organisms that reproduce among itself and produce offspring. The scientific name is used by scientists all over the world for ease of communication. After all, it is very important to be specific in science. For example, the scientific name of the cougar/mountain lion/puma is Puma concolor. The name cougar/mountain lion/puma refers to the animal’s common name. Organisms can have many common names used by the public, but when scientists are referring to them, they use the scientific name. Domain Kingdom Phylum Class Order Family Genus Species
Climate change affects the entirety of the earth’s surface, and nowhere more so than our oceans. While our seas cover about two-thirds of the earth’s surface they absorb over ninety percent of the additional heat attributable to global warming. Both land masses and bodies of water absorb and reflect solar radiation that rebounds off of the greenhouse gases trapped in our atmosphere, but the latter is generally more absorptive and holds on to heat longer due to differences in physical properties. This of course has led to increases in global seawater temperatures, which has and continues to endanger several aquatic species. This article will examine one of those species and go over human efforts to preserve it.
In this lesson, we learn about the 3 shunts of fetal circulation: ductus arteriosus, ductus venosus, and foramen ovale of the fetal heart: functions, medical significance, when they close, medical complications, and remnant ligaments.
Navigating through the trials and tribulations of school, high school or college, is a feat on par with walking a tightrope. The stress and change in your life makes you feel like you are constantly about to drop. Too much push and pull to one side, and you […]
Finals, midterms, SAT, ACT, Accuplacer, the list of tests we have to prepare for is seemingly endless, and the studying that is required for each one appears to be a long and arduous process. Yet it doesn’t have to be that way. By organizing your time and your workspace, using effective study and review methods, and sticking to a study cycle, you can navigate through the process of studying as painlessly and as quickly as possible. Here are Top 5 Study Strategies – Study Smarter, More Effectively, Not Harder
Mental health is incredibly important in our day-to-day lives and must be brought up during this time of great pain and suffering. Below are top 5 tips on how to maintain healthy mental wellbeing and ways we can all reach out and help our communities.
Every wondered what was the history of and use of Mummies? Look no further: Educational article on the use of mummies as medicine, the unique mummy business and sales throughout history.
Ever wondered how plants grow or survive? In this educational lesson, we learn all about plant hormones, including gibberellin, auxin, cytokinins, ethylene, and abscisic acid.
For the average person, washing their hair every day or every few days is a matter of hygienic preference rather than necessity. Unless their work or pastime brings them in contact with dirt or involves physical exertion, it is unlikely that their hair would go from being clean to truly dirty in the span of twenty-four hours.
So, what is the true science behind our “dirty” hair and the ingredients in our shampoo?
When does a baby say its first words, Mama and Dada? When does a baby learn to stand up and walk on its own? Is it normal for an infant to develop stranger anxiety at 9 months? In this quick and easy-to-understand lesson, we review the infant developmental milestones at 1 month, 6 months, 9 months, 12 months, 2 years, 3 years, and 4 years. This lesson includes high-yield USMLE quick take-home points, high yield summaries, and practice test questions/answers on infant developmental milestones.
For all its complexities, and thanks in part to them, English is a highly versatile language. Several other languages have government affiliated academies that dictate their proper usage, voting on things like the addition of new words. No such body exists for English, making its development less top-down and more of a dialogue between those at the top and the general masses. One area where this can easily be seen is with loanwords.
Motivational Quote of the Day: “You are never too old to set another goal or to dream a new dream.” ~C. S. Lewis
Motivational Quote of the Day: “You are never too old to set another goal or to dream a new dream.” ~C. S. Lewis~ Want more of our free content and motivational quotes of the day? Join Us! Subscribe for free or like us on Facebook.
You probably go to sleep most – if not all – nights. You probably have dreamt during many of these nights. And you might feel rested every time you go to sleep. Yet did you know about the complex mental processes that happen every time we go to sleep?
Circulatory System: Heart Structures and Functions; Blood flows through the heart in the following order: body –>inferior/superior vena cava –> right atrium –> tricuspid valve –> right ventricle –> pulmonary arteries –> lungs –> pulmonary veins –> left atrium –> mitral valve –> left ventricle –> aortic valve –> aorta –> body…