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oyla-science.com

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#62018

(15)Â JUNE

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ISSN 2537-7744 ISSN 2537-7744

JUNE 2018

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MATHEMATICS

TECHNOLOGY

Logic versus Intuition

Space Trash: how great a threat is it?

p. 4

p. 52

The history of

Dwellings p. 60

What is an

Irrational Number? p. 8

CHEMISTRY

The Polymer

Century p. 16

BIOLOGY

Why do we need

Cell Cultures? p. 30

How does a cell become an organism? p. 36

MEDICINE

How do Allergies develop?

p. 44


ECOLOGY

How can we Preserve Biomaterials? p. 66 The history of

Concrete

p. 90

ECONOMICS

What is a Budget? p. 72

MEGAPROJECT

What does the NASA’s Mars rover consist of ? p. 50

SKEPTIC

What is hidden from us? p. 80

SOCIETY

The most Exciting Bets in history p. 84


M AT H E M AT IC S

Logic Versus Intuition Why do so many people not like maths? One of the most common answers is: “because it’s dull.” In every “obvious” situation, they make you prove something! But “obvious” conclusions often turn out to be erroneous, and remain so for a long time, because we are intuitively convinced of their “correctness.”


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#15 J UNE 2018

Geometric Proof m Let √2 = n , where m and n are the smallest numbers possible that do not have any common divisors. Then 2n² = m², that is, the area of the square with side length m is equal to the sum of the areas of two squares with sides n. If the smaller squares are placed in opposite corners of the large square, their intersection will give us a new square with side m − 2(m − n) = 2n − m. The uncovered areas of the square are also squares with side m − n. From the equality of the area of the square with the side m and the sum of the squares with the side n we get that the area of the section of the plane where the squares 2n − m overlap is equal to the area of the uncovered sections inside the square, that is, (2n − m)² = 2(m − n)². It follows that √2 = m −n That is, the number √2 can be represented as a ratio of integers less than m and n, which were the smallest numbers possible! Hence, we have found a contradiction.

m n

n

(m–n)2 (2m–n)2

=

+

(m–n)2

Algebraic Proof If the number √2 can be expressed as a fraction, then we can write it as a ratio of the natural numbers a and b, b a , when a and b do not have common b factors (which means that the fraction is irreducible). namely √2 =

We multiply the equality by b and raise both sides of the square. We obtain 2b² = a².. Since the left-hand side of the equation is even, then a² must be divisible by 2,, and this is possible only for an even a. If a is even, we can represent it in the form a = 2с. But then, 2b² = 4с²,, from which it follows that b²= b² = 2с², and this entails the parity of the number b.. So, we have obtained that a and b are  are even numbers, but this contraa dicts the statement that the fraction b is irreducible. This contradiction proves the impossibility of representing √2 as a fraction.


M EG A PI XEL

An astronaut’s eye view on NZ In this 2006 image from the STS-116 mission, astronauts Robert Curbeam Jr. and Christer Fuglesang venture outside of their vehicle, one of three such planned missions during construction of the ISS. The islands in the backdrop are none other than our own lovely New Zealand!


CH E M IS T RY

THE POLYMERIC AGE

What are the threats to the environment?

P

eople have used polymers since the Stone Age wool and leather contain proteins cellulose is the main component of fabrics, papyrus and paper. Throwing out such materials would not make one concerned for the environment because they decompose fast. At the beginning of the 0th century, mankind mastered the manufacturing of artificial and synthetic polymers. The products proved to be light and durable, but… The coming of the polymeric age was overshadowed by the failure of nature to expediently get rid of such compounds. As a result, “man-made” polymers get piled up in giant quantities in landfills, and scientists are looking for ways to save the Earth from pernicious plastic.

Chain Molecules olymers, despite their low specific gravity, have a large molecular weight. Certain elements in these compounds — cross-links — are repeated periodically. In fact, polymers are old as life itself. The essential components of living systems are such polymers as proteins, nucleic acids and polysaccharides. These polymers are called natural. Those created by man — artificial and synthetic.


CHEMISTRY

There is a possibility that some organisms that evolutionally adapted to extracting microelements from synthetic polymers will come about. The list of bacteria is growing. In 0 , a bacterium processing polyethylene terephthalate (Ideonella sakaiensis) was discovered, and in 0 the list of creatures with unusual food habits was supplemented with a highly organi ed organism — the wax moth larva Galleria mellonella). It digests polyethylene, splitting it to ethylene glycol. n the one hand, it’s good that there are ways of biological processing of plastic. n the other, they are fraught with danger such organisms may eventually feed not only on waste, but also, for example, on polymer insulation of wires, plastic water supply communications. And this may cause accidents and man-made disasters.

Turtle coming to breathe to the surface in t e iddle o rubbi oatin in t e Atlantic Ocean

A Grey Seal at Horsey Beach in England, tragically caught in a ection o fi in net an u ettin ite t at a re orted to local animal welfare.


M AT E RI A L S S CIE N CE

WIN G ED ELEMENTS Aluminium, the most widely found metal in the earth’s crust, was generally more expensive than gold half a century ago, although its reserves are hundreds of millions times ampler. The precious aluminium helped the man climb into the sky. However, it seems that soon it may relinquish the title of “winged metal” to titanium and … carbon.


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#15 J UNE 2018

VACUUM, STOVE AND CARBON The carbon structures are manufactured by placing carbon fabric or fiberglass in several layers in a form of wood, gypsum or steel. Then the prepreg — an epoxide-impregnated semi-finished product — is made. The epoxy resin is converted into a solid polymer in an autoclave, where it is kept under pressure for several hours then it is ground up and sent to an assembly line. Carbon technologies have entered almost all spheres of mechanical engineering they are used in the manufacturing of car bodies, boat hulls, and strength elements of aircraft.

cheaper. That’s why polymer composite materials from carbon fiber have found their way into aviation. The term “black wing” today means not the color of the skin, but the material of the wing’s load-bearing structure. The manufacturing process is simple the carbon fiber is laid in a mold, impregnated with a filler — a special resin — and sent to a huge (the si e of the wing) curing oven. As a result, the aircraft gets a light and extremely strong wing, which is resistant to corrosion, however somewhat more demanding in maintenance than a usual wing. To make the most of the weight reduction (without reducing the strength), a vacuum diffusion method is used, when the carbon wing billet is packaged in a bag, the air gets pumped out and the bag is filled with the resin. The billet will absorb as much resin as needed, and the engineers will only have to send it to the furnace. A quarter of the modern two-deck air giant Airbus A 0 is made of carbon

composites, — of A E material, which is a “sandwich” made of aluminium and a polymer composite. A E combines the best properties of “winged” metals and promising composites — perhaps, such materials are the future. The elements “with wings” allowed mankind to climb into the sky, and then

into space, but composite materials have been stealing leadership. nly the emergence of new economically and environmentally friendly technologies for Al and Ti production can restore these elements to previous positions in the celestial industry.

Airbus A380. The airliner structure is about co o ite aterial . arbon co o ite and fiber la are u ed in the design of the wings, center-section and tail unit.


BIOLOG Y

Cell Cultures


31

#15 J U NE2018

Micrograph of a HeLa cell line

Imagine that you are a scientist studying a very rare animal which resides in the jungles of the Amazon. You need not only to study its external and internal anatomy but also to learn what is written in its genes. If you really want to find out everything about the organism, do you need to take a new sample — for example, cutting off a bit of its ear — all in the name of biomaterial? Of course not. Cell cultures — in vitro (in a test tube) models of living organisms — come to the rescue.

How To Make Them The most accurate model of separate tissues is actually primary cultures, which are taken directly from the organism. A piece of tissue is mechanically destroyed using enzymes (for example, collagenases). The structure of the majority of tissues is formed thanks to the so-called extracellular matrix, in which, like bricks in cement, cells are fixed. Collagenase destroys collagen, the main component of this matrix. This is how you get a culture where you can observe separate cells. The free cells that you receive fill the space of a flat-bottomed dish (a Petri dish,

a glass plate, or a flask for cultures) and a nutrient mixture containing hydrogen, salts, amino acids, vitamins, fatty acids, and proteins are added. Besides that, cells need to be in carbon dioxide gas. CO2 dissolves in the surroundings, forming bicarbonate ions, HCO3-, which increase the acidity (pH) of the medium into a range that is comfortable for cells, a pH of 7.2–7.4. To avoid devastating jumps in acidity, the cells in their nutrient solution are placed in a CO2 incubator, which creates a concentration of CO2 atoms in the air that is suitable for life.

A DIAGRAM OF THE PRODUCTION OF PRIMARY CULTURES

Enzyme treatment

Blended tissues

Mechanical grinding

Explant

Implanting in a culture medium Organ


BIOLOG Y

How a cell turns into an organism

At the very beginning, we are all just a single cell — the zygote. It forms as a result of merging of two other cells: male and female gametes. The zygote divides, and its direct descendants, cells, look the same for a certain time after the so-called cleavage. Further along, they become the building material for absolutely different organs: brain, heart, bones. How do cells figure out who to become and where to grow?


37

#15 J UNE 2018

Preformism and epigenesis Back at the time when virtually nothing was known about DNA and other biological molecules, the processes underlying the transformation of the zygote into a multicellular embryo with various (or, as they say, differentiated) tissues and organs were totally obscure to scientists. That’s why there were many fantastic explanations of how the individual development of the organism might progress prior to its birth or hatching. It was tempting to think that the embryo “knows” everything from the start. Such a theory did not require either chemical or physical data or even biological. For example, there was an opinion that one of the cells which partake in the formation of the zygote carried the plan for a whole adult organism. Naturalist and inventor Antonie van Leeuwenhoek, who first saw male sex cells, spermatozoa, under the microscope, decided that they were the ones possessing the plan. Those who supported his point of view were referred to as animakulists. But there were others who placed the structural data in the egg cell, the so-called ovists. However, it is not so important, whose gamete, according to the scientists of the past, contained a miniature little man — a homunculus. What matters is that this concept is incorrect. Look: if in every male germ cell (spermatozoid) came with a complete future person, he would also have spermatozoa inside, only much smaller ones. And so on. And if the embryo were female, how would she pass on information about the future looks to their descendants? Later, even with the development

Ovists placed a er on bod lan in an e

iniature uture or ani to ani a uli t

accordin

of microscopic technologies, no homunculi were found inside the spermatozoa. So the assumption failed not only theoretically, but was also upended by practical research. Despite the obvious inconsistencies, the assumption that the fate of each cell of the embryo is predetermined, and the development of the embryo is deterministic in general, was popular for a long time, especially in the 17th–18th centuries. It had an alternative name — preformism, and its supporters were called preformationists. The scientific substantiation of preformism sounded like this. Many ovules contain a solid supply of nutrients — a yolk. The yolk may be non-uniform. Male reproductive cells, at least in animals, do not participate in the formation of this cache, and therefore do not change the composition of the yolk and the location of substances therein. After fertilization, the zygote cleaves dividing into cells, but not growing. Thus, each cell formed during the cleavage process (now they are called blastomeres) gets a portion of the yolk, slightly different in composition from what its neighbours receive. Therefore, the properties of the descendants of various blastomeres differ. Some are capable of giving rise to the outer layer of cells of the embryo, ectoderm, others to the inner, endoderm, and the third to the middle, mesoderm. When the cleavage ends, the cells begin to grow, but none of them has all those components of the original whole yolk. Therefore, their properties will never be similar. Sounds all right, at least more intelligible than a homunculus story.


M E DICIN E

WHAT CAUSES

ALLERGIES? Plasmatic B-cells releasing antibodies

You can feel the spring in the air again! The days are getting longer, the wind doesn’t nip at your nose anymore, snow melts, and streams run down the asphalt in the cities that were so chilly not long ago. But there are people who have to face new challenges when warm spells come. Every year, it’s as though they’re preparing for war: they stock up on drugs, buy medical masks. These are highly allergic people, and spring poses a serious threat to them.


#15 J UNE 2018

51

e rover orn eel are t e ain ri endan erin t e i ion co letion alt ou t eir current tatu fit in t e calculation o en ineer . n all eel o t e device t ere are t ree ori ontal tri it ole ic o t e letter J, P and L (·—— ·—· ·—·· . i i an abbreviation o t e et ro ul ion aborator t e creator o t e rover.

e ar rover fir t elfie a t ta en on ctober on t e 4t da o it ta on ar . an to t e e t e o i a e cienti t on art can detect al unction in t e device.


T ECHNOLOG IE S

S PAC E

DEBRIS The

Kessler

Syndrome

In 1978, the consultant of the NASA’s Environmental Protection Agency Donald Kessler predicted, with a surprising accuracy, the situation the modern astronautics has eventually found itself in. This was the reason scientists immortalized his name in the term “Kessler effect” which describes the impossibility to take advantage of the near space because of orbital debris. Sounds incredible?


53

of astronomy. And finally, the real glory came to the scientist with the discovery of 00 E — a mysterious body detected on that very day, the rd of September. The candidate for an asteroid moved along a very elongated geocentric orbit, which is characteristic of small celestial bodies captured by the Earth’s gravity. And this event (the capture), as the calculations showed, had happened recently. The fact is that high near-Earth orbits are extremely unstable all more or less massive objects are quickly pushed out of them due to the attraction of the Earth- oon-Sun system. The first thought that occurred to specialists from the international inor lanet Centre, where the information about 00 E was received, was this “Is it really them ” They meant aliens. The basis for such a strange conclusion was the unusual composition of the object. Spectral analysis revealed an anomalously high content of titanium dioxide, known to us as … whitewash. y the way, humanity actively uses it in paints and varnishes as an anticorrosive additive. The reality turned out to be mundane the mysterious “newcomer” was S-IV  — the third stage of the Saturn V rocket of the lunar expedition Apollo . ack in the autumn of , it was dropped in the wrong place and at the wrong time and entered a near-Earth orbit with a very large eccentricity. ue to the fuel overrun, the stage, intended for the injection of the command and landing modules into the circumlunar orbit, could not reach the required speed to be pushed to the heliocentric orbit. ortunately, the 00 E

J002E3

White Stranger n September , 00 , the Canadian astronomer of Chinese descent illiam eung took over a watch at the observatory esert Eagle, recently built in the middle of the Ari ona desert. Now, we should say a few words about the scientist’s personality. irstly, ill, globalist to the bone, is his own boss the observatory and all the equipment it it is his property. Secondly, ill eung is a real superman in terms of the sphere of his scientific interests in less than 0 years he discovered more than 000 objects and became one of the most successful asteroid hunters in the history

Earth

Moon

The yellow line marks the trajectory of J002E3. Before leaving the geocentric orbit, the object made six revolutions around the Earth.


T ECHNOLOG Y

Home 1.0. The History of Dwellings OYLA | REAL ESTATE AGENCY

In the beginning, our ancestors lived in… nests. Later they moved to caves and huts from bones. Then they made dugouts in the hills. And then they came one after another: castles, palaces, skyscrapers…

It’s a nest. A most ordinary one made from twigs and grass. Scientists believe that our ancestors, Australopithecus, probably built them like modern anthropoid apes (monkeys with bodies similar to ours) do. Did you know that they lived in nests? Well, not live but rather spend nights. Monkeys are always on the move — they wander from place to place and build a new nest every night. Chimpanzees and orangutans make them on trees, and hefty gorillas set them up right on the ground (tree branches simply break under their weight). Those were not proper dwellings, but merely “beddings.” Real dwellings appeared when our ancestors wanted to make something stronger, more durable, bigger. But why? There are many versions. Among the most convincing is a simple one. The ancestors gradually mastered hunting, and not only gophers and meerkats (mongooses that inhabit the human ancestral home — Africa), but also a larger “catch” began to come into their deft hands. For example, elephants. You can’t eat it at one sitting. What can be done? Right. Share it with a friend. Or rather, with friends — a big family (ancient people lived in groups of 20–30 people). And still, there’s plenty left. And then predators are closing in from all around — they also want a piece of fresh meat. The only solution is to make a feast of feasts. That is, to set up a camp. For a few days, no more (need to go further, keep hunting), but all the same. Branches, stones, straw — anything that is at hand will protect them from predators.

Beginning of Time


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#15 J UNE 2018

The National Museum of Natural History in Paris is the largest French museum dedicated to the natural sciences achievements. It has several zoos, a botanical garden, a marine biology station, an evolution gallery, and many other facilities

Almost completely exterminated 100 years ago, the European bison gradually returned to its former habitats due to the efforts of environmentalists

The Persian fallow has successfully been reintroduced from the breeding nursery in Carmel to the wildlife in northern Israel

ECOSYSTEM Ecological system is a biological system — an assemblage of living organisms that are connected with each other by a cycle of matter and energy, as well as by their habitat. It may be a drop of water, or it can be the planet as a whole.

Reclaiming that Which Was Lost eople started to think about how to take care of and restore ecosystems less than a hundred years ago. In the middle of the 0th century, the first large-scale programs were initiated to get animals and plants back to their original habitats. y the 0s, there were no European bisons left in the wild (Bison bonasus). They were almost completely destroyed during the irst orld ar and the Civil ar in ussia. Scientists searched for surviving bisons in oos and private menageries, set up special wildlife reserves, mated animals according to genetics rules, in order to avoid the consequences of closely related breeding, which leads to the accumulation of harmful mutations. In , the first herd was let out into the wild and settled in a reserve on the border of modern oland and elarus. The reintroduction programs are now widely applied — one of their most active participants is Israel. There are more than 0 nature protection ones in the territory of this small state The fact is that careless land use in these parts leads to the formation of lifeless deserts. To stop the advance of sand and to win back the priceless square meters, Israel almost has been running

environmental programmes from the very moment of its foundation in 4 . In half a century, the following species have been restored: the dorcas ga elle (exterminated by hunters in 0)

• white ryx antelope (it was not encountered in the Negev • the and Arava deserts for more than 00 years) ersian fallow deer (almost completely extinct by the • the beginning century, now reintroduced in the north of the country).

Przewalski’s Horse Mystery The technological development brought new possibilities for isolating and preserving biological material. New types of biological collections appeared (today, for example, scientists preserve viable cells in liquid nitrogen, create digital genetic databases). The old ones can be used to extract much more information as well.


ECONOMIC S

Keeping within means Our BUDGET does not allow us to buy a bicycle this year!

Our BUDGET does not provide for a trip to the sea this summer!

Expenses for car repairs are beyond this month’s BUDGET!


L E A RNING

LET’S LEARN

CHINESE ‘To learn a language is to have one more window from which to look at the world.’ So states a Chinese proverb and this is, without a doubt, true. Learning a new language opens up a world of new frontiers and possibilities, allowing us to talk to new people and explore new experiences. Dr Svetlana Chevenko wants to make this a possibility for everyone and has done so by developing a revolutionary method for learning Chinese that is accessible to all, from school children to adults. Dr Chevenko, a specialist of East Asian languages who came to New Zealand in the 1990’s, has developed her teaching method using her experience in the fields of applied linguistics and artificial intelligence. Chinese, the world’s most widely-spoken language at 1.3 billion speakers, is very different from most other popular languages such as Spanish or English. Due to these differences, Dr Chevenko has developed a method for learning Chinese that is tailored to its uniqueness. The basis for her method involves breaking down studying into two parts: speaking the language and reading and writing it. This begins from the very first stage of learning Chinese. She has created several crash courses, including ‘Learning Chinese Characters the Revolutionary Way,’ ‘50 Most Frequently Used Chinese Characters,’ and ‘Chinese Characters for Children,’ among others. Her

method incorporates the etymology, or origin, of various Chinese characters, helping students to remember them easily. For example, the characters , , mean “one,’ ‘two,’ and “three.” “One” ( ) comes from the idea of ‘horizon,’ where the sky and earth become one. “Two’ ( ) involves two different elements, the earth and sky. Finally, ‘three’ ( ) portrays sky, earth, and people between them. The characters for tree and forest can also be looked at in this way.

CHINESE NUMBERS

1

2

3

4

5

6

7

8

9

10

11

12


SKE P T IC

Hiding From Us Whenever something happens in the world, there is always someone at fault. And if this “something” is on a global scale, it obviously didn’t happen without some kind of conspiracy. Are doctors advising that you be vaccinated? They want to cash in on vaccine sales! A man walked on the moon? Falsification, of course! And worldwide surveillance? We are all in danger … until we turn on our common sense and start thinking critically.


S O CI E T Y

BET ON

TRUTH

Truth, as you know, is born in arguments, and betting on it can also bring a reward. Of course, it is so darn nice to rub it in the opponent’s face with the phrase “I told you!” But getting the prize is also great. And who appreciates the truth more than scientists?

DISCLAIMER We do not promote gambling! You and your friends can argue which of you will go to Mars or receive the Nobel Prize, but it isn’t advisable to bet away the money that’s been put aside for lunch.


T ECHNOLOG Y

THE FOUNDATION OF CIVILIZATION

From the Egyptian pyramids to smart blocks with temperature sensors — concrete and related technologies have come a long way since they emerged. Soundproof high-strength buildings have become a part of our life. And the history of concrete is full of trials, mistakes, and brilliant solutions.


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OYLA Youth Science, June, 2018, preview  

What is the most important organ in the human body? In this issue we will talk about the heart: an indefatigable and faithful worker! We tel...

OYLA Youth Science, June, 2018, preview  

What is the most important organ in the human body? In this issue we will talk about the heart: an indefatigable and faithful worker! We tel...