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Aphorisms of famous people. The most popular quotes by famous authors

Big encyclopedia. Questions for quiz and self-education. Simple answers to complex questions

Riddles, puzzles, trick questions. Test your resourcefulness and sense of humor!

Online quiz. Interesting questions on any topic

Entertaining experiences at home. Interesting physical and chemical experiments with illustrations

Do you know that... To help the erudite. Database on the history, geography, biology, science, technology, sports, culture, traditions of the peoples of the world

visual illusions. Are you sure you really see what you see?

Stories from the life of a radio amateur. True cautionary tales told from 2002 to 2024 by site readers

Winged words, phraseological units. Meanings, history of origin, examples of use

Cultivated and wild plants. Legends, myths, symbolism, description, cultivation, methods of application

palindromes. Magic phrases that read the same from left to right and vice versa

Popular Latin words and phrases. The most famous set expressions in Latin

Proverbs and sayings of the peoples of the world. Popular wisdom in short sayings

Assembling the Rubik's Cube. A simple guide to solving the Rubik's Cube with detailed illustrations

Crosswordist's Handbook. Convenient word search by mask

Spectacular tricks and their clues. Impressive magic tricks with detailed explanation of secrets

Guess the country by its flag. Online game about flags, countries and capitals

Wonders of nature. An exciting journey around the world


Random articles


Theory of Illusions


Examples of illusions


Volumetric gif-animations


A random story from the life of a radio amateur:

I sit somehow at the client's house, poking around on the TV. He passes by and says: "You are watching, do not forget something on the TV when you close it. A soldering iron is there or something else." I smile: "Don't worry, I'm a TV technician, not a surgeon!" Well, I made a telly, received the money and went home. And on the threshold of his house, he suddenly remembered that conversation. And he realized: where is my device? I go home, climb into the suitcase: it’s true: the device is not visible! And then the phone rings. I pick up the phone - the same customer: "Sasha, you forgot your device with me." My heart skipped a beat.. "Where?" - I ask. "Really on TV???" "No, what are you! On the table!"
Other stories from the life of radio amateurs | Random fun story

Random fun puzzle:

How many different digits must be used to write the number 100?

Other fun puzzles | Random fun puzzle

Random Question Quiz Online:

"And God said, Behold, I have given you every herb yielding seed, which is in all the earth... This shall be food for you." This quotation from the Bible, given in the courtroom, did not help the Zambian student to avoid a sentence - a year and a half. For what?

Other Quiz Questions | Random five questions

Random aphorism:

"Ни одна вещь не возникает беспричинно, но все возникает на каком-нибудь основании и в силу необходимости" (Демокрит)
Other aphorisms | Random aphorism

Random proverb:

За пустым столом молитвы не бывает. Лакская пословица
Other proverbs of the peoples of the world | Random proverb

Random phraseological unit:

If this isn't true, then it's well thought out.
(Used as a humorous and ironic commentary on plausible, but still dubious information)
Italian folk saying. It is first found in literature in the work "Worlds" (mid-1585th century) by the Italian writer Antonio Francesco Doni, then in the work "Heroic Spirit" (1548) by the Italian scientist, philosopher and poet Giordano Bruno (1600-XNUMX).
Other phraseological units | Random phraseological unit

Random phrase in Latin:

In partem salari. - В награду за труды.
Other phrases in Latin | Random phrase in Latin

Random fact "Did you know?":

A quarter of Europeans, according to surveys, believe that artificial intelligence can be trusted to make important political decisions.
Other Facts "Did You Know?" | Random interesting fact

Random article of the Great Encyclopedia for Children and Adults:

When were cats domesticated?

Cats are very ancient animals. Cat remains have been found that are millions of years old!

The domestic cats that we know so well are descended from the wild cat, but we don't know which one, because that was too long ago. Perhaps all varieties, or breeds, of cats are descended from two or three small wild cats that existed in Europe, North Africa and Asia thousands of years ago.

It is believed that they were first tamed about 5000 years ago. We know that 4000 years ago the Egyptians had tame cats. People worshiped them, and some deities were depicted with a cat's head. Cats were even sacrificed.

When a domestic cat died, the Egyptian family and all servants shaved their eyebrows and went into mourning. The death of the temple cat has put the whole city in mourning. Many mummies of these animals have been found, made in the same way as the mummies of pharaohs and noble courtiers. The only payoff for killing a cat was death!

In Europe before 1000 AD. e., probably, there were no tame cats. In ancient times, Europeans treated these animals in a completely different way than the Egyptians. It was believed that a devilish spirit was imprisoned in it. The Devil was often depicted as a black cat, and it was believed that witches turned into cats.

Different breeds of cats, and just individual individuals differ from each other as much as dogs. It is easy to distinguish longhaired cats from shorthaired ones. Of the long-haired, the most famous are the Angora and Persian.
Other articles of the Great Encyclopedia | Random article of the Great Encyclopedia



Latest news of science and technology, new electronics:

Improving the efficiency of PbS quantum dot solar cells 14.06.2024

The latest solar technology research represents a significant breakthrough in improving the efficiency of PbS quantum dot solar cells. This method, based on the use of pulsed light, offers promise for simplifying the production and expanding the applications of these cells. A research team from the Daegu Gyeongbuk Institute of Science and Technology has developed an innovative method that uses pulsed light to improve the electrical conductivity of PbS solar cells. This method can significantly reduce the processing time required to achieve similar results. PbS quantum dot solar cells have significant potential in solar technology due to their photovoltaic properties. However, the formation of defects on their surface can reduce their performance. The new method helps suppress defect formation and improve electrical conductivity. Using strong light to complete the process ... >>

Magnetic Power Bank 5000mAh 14.06.2024

Huawei introduces a convenient and multifunctional charger to the market - Huawei SuperCharge All-in-One Magnetic Power Bank. This magnetic battery allows you to quickly and conveniently charge your Huawei phone anywhere, anytime. With a thickness of just 11,26 mm and a weight of 141 grams, this portable power bank fits easily into a pocket or bag, making it ideal for travel and everyday use. Despite its compact size, this battery provides enough power to charge your phone on the go. The new product supports wired charging with a power of 25 W and wireless charging up to 15 W (and up to 30 W when connected to an adapter), providing fast charging for both the power bank itself and other devices. The battery is compatible with various fast charging protocols such as SCP, UFCS and PD, making it ideal for a wide range of devices. The power bank is also compatible with Huawei phones that support wireless charging. ... >>

Changes in a father's brain after the birth of a child 13.06.2024

A recent study conducted by scientists from the Hefei Institute of Physical Sciences of the Chinese Academy of Sciences found interesting changes in the brains of men after becoming fathers. These changes were associated with involvement in child care, sleep problems, and mental health symptoms. Scientists found that men who became fathers experienced a loss of brain volume after giving birth. This volume loss was associated with greater involvement in parenting, sleep problems, and mental health symptoms. Researchers have found significant changes in men's brains between the prenatal and postnatal periods. In particular, there was a loss of gray matter volume, especially in parts of the brain responsible for higher functions such as language, memory, problem solving and decision making. Men who paid more attention to their children and spent more time with them lost more gray matter in their brains. This also affected their mental health ... >>

Random news from the Archive

Gene rejuvenation 30.04.2016

Elizabeth Parrish, CEO of US research company BioViva, has become the first person to successfully test anti-aging gene therapy.

Despite the fact that we notice the first age-related changes by external signs, aging processes are formed and develop inside - at the cellular level. The ends of chromosomes are called telomeres. They do not carry genetic information, but protect the chromosomes, acting as a kind of "buffer" against wear and tear. However, each time a cell divides, the telomeres gradually decrease until they are so short that they can no longer protect the chromosomes. As a result, the cell ages and can no longer perform its functions.

An enzyme called telomerase is able to complete short telomeres. Aging body cells, thanks to telomerase, again acquire the ability to divide, like young and healthy cells. So far, the telomere lengthening technique has only been tested in cultured cells and laboratory animals.

The first experiment to test a unique rejuvenation technique on a person started in September 2015, when 44-year-old Elizabeth decided to undergo two experimental gene therapy courses developed by her employees to slow down aging. The first course is designed to prevent loss of muscle mass with age, and the second is aimed at increasing the production of telomerase. The injections were given to Elizabeth in Colombia as the drugs are not approved by the US Food and Drug Administration (FDA).

Now the first results of gene therapy have become known - and they are stunning! The analyzes showed that the drugs actually stopped the shortening of telomeres. Leukocytes in Parrish's blood became biologically younger, and telomeres "lengthened" by 20 years. The discovery of BioViva has attracted the attention of both scientists and investors, while the experiment continues and the researchers carefully monitor Parrish's health.

Other interesting news:

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News feed of science and technology, new electronics


Interesting materials of the Free Technical Library:

▪ section of the Electrician website. Article selection

▪ article by Quintus Curtius Rufus. Famous aphorisms

▪ article Which of the seven Wonders of the World has survived to this day? Detailed answer

▪ article Field horsetail. Legends, cultivation, methods of application

▪ article Indication of the operation of the apartment bell. Encyclopedia of radio electronics and electrical engineering

▪ article We heat a faceted glass. physical experiment

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