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» Glavni naslovi

SUMMARY

 

Summary

TOPIC OF THE ISSUE

Periodic Table of the Elements
From 56 to 118

150 years ago, at the time the first table of the Periodic Table of the Elements was created by Russian chemist Dmitry Mendeleev, few could have predicted the extent to which this knowledge would be disseminated. Mendeleev enrolled 56 elements - today there are 118! These elements are all around us, and presence of some of them we can even sense directly. Some elements can be found in the palm of your hand, others are difficult to "catch", some last only for a few seconds, and presence of some other requires very complex scientific equipment. The practical purpose of this systematization is immeasurable. Whatever happens and is tested in chemistry, the periodic table of the elements is what studies are based on, it is the basis of all scientific discoveries and technological advances. Although, at the beginning of the 20th century, Mendeleev was nominated for the Nobel Prize in Chemistry, he did not receive it for seemingly prosaic reasons: there was disagreement with the Committee for the award and ... the award went to another scientist! However, today, when the Table of the Periodic Table of the Elements is mentioned, the first word to follow is Mendeleev's last name.

 

MEDICINE

Coronavirus 2019-nCoV

The epidemic of a new virus, from a large coronavirus family, with an outbreak in one part of China, has been the focus of the World Health Organization (WHO) for months. As it spreads to other parts of the world, prof. Dr. Darko Nozic, an infectologist at Bel Medic, explains what is so far known about this pathogen, and what WHO recommends as the most effective protection. Coronaviruses are actually a large family of viruses that can be found in both animals and humans. In humans, coronaviruses cause respiratory illnesses ranging from the common cold to serious illnesses such as Middle Eastern Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Named for crown "growths" on their surface, coronaviruses were first identified in humans in the mid-1960s. Humans are usually affected by four known types of coronaviruses: 229E, NL63, OC43, and HKU1. Sometimes, however, it happens that coronaviruses that occur in animals evolve, infect humans, and thus become new human coronaviruses. Three such recent examples are SARS-CoV, MERS-CoV and 2019-nCoV. The new, or "latest," coronavirus, 2019-nCoV, is the same virus family as SARS-CoV, but was not identified in humans before the Wuhan epidemic in December 2019. On February 11, the World Health Organization released the official name COVID-2019 for the disease caused by the new coronavirus2019-nCov.
 

 

MEDICINE

Jaw orthopedics

Preventive dental examinations, from a very young age, are the best way to maintain the health of the mouth and teeth, so the habit of regular visits to the dentist should be built from the second or third year of the child's life, and no need for dental interventions. It is equally important, however, that from the age of four or five - and at the latest before entering the school, when the milk teeth usually begin to be replaced by permanent ones - that the orthodontist, a specialist in orthopedics of the jaw, becomes involved. Timely orthodontic examination will not only ensure the future health and aesthetics of permanent teeth, but will prevent the development of early craniofacial anomalies, prevent problems with the jaw joints and ensure good processing of the food that underlies digestive tract health and overall health. Although orthodontic therapy today can be applied at any age - even at a very old age - it is the most valuable, simplest, fastest and cheapest in children. According to Dr. Predrag Lazovic, a specialist in orthopedics of the jaws, consultant at Belgrade's Bel Medic General Hospital, its supreme importance is its timely effect on the growth and development of permanent teeth and jaws, as well as on inter-jaw relations. The correct position of the teeth in the jaws and their proper contact with each other ensure proper bite, which reduces the load of individual teeth and maintains the health of the paradontium (supporting tissue of the teeth), and therefore prolongs their lifespan.

 

MEDICINE

Tinnitus - phantom sound in the ears

Subjective tinnitus - without the objective presence of appropriate external sound - is the most common form of this largely harmless condition. If it is found that there are no more serious causative agents, but bothers the affected person very much, doc. univ. dr Liliana Cvorovic, Bel Medic consultant, recommends TRT, tinnitus habituation therapy. Tinnitus is illusion of sound perception - most commonly buzzing, whistling, chirping and other similar sounds - without the objective presence of appropriate external sound. Some people hear this illusory sound only in one ear, and some feel that it comes from both ears, that it is "in the head," or that it comes from a distance ... In this case, "tinnitus" may be constant or intermittent, stable or pulsating. In addition to subjective tinnitus, the most common form of this largely harmless condition, there is also the so-called pulsating tinnitus, in a rhythm of the heartbeat; since it may also originate from so-called somatic (bodily) sounds such as murmur of the blood circulation or heartbeat, objective tinnitus is another form of it that can really be heard with the help of a medical stethoscope. Although often associated with hearing loss and hearing loss, tinnitus does not cause hearing loss, nor does hearing loss cause tinnitus. Moreover, many people with tinnitus have no hearing problems at all, and there are even cases of hypersensitivity to external sounds.

 

EPIGENETICS

Genes and organic overturning

We know we look like of our parents. We mostly understand that it has to do with something that was written in their genes and then passed on to us, the offspring, at conception. We know it's hard to inherit blue eyes if one of the parents has black, and we remember a joke about Einstein, who was allegedly approached by some pretty girl with the idea that it would be wonderful for the two of them to have a kid that is nice like her and smart like him. To this he answered: and what if that child inherits your brain and my beauty, then what shall we do? As complicated as the rules of inheritance are, what we know for sure is that we are born with a record that determines what kind of human being we will develop. And we know that record is in our genes, and genes in all our cells. What majority missed is that genes are really just fragments of long chains of DNA molecules, accounting for only 2% of the total genome. This means that only 2% of our genome has been used to mark down how a human being will be constructed from a single fertilized egg, and then for the complete functioning of the organism. The remaining 98% were just unnecessary genomic junk.
 

 

MYCOLOGY

MDS - what is it?

Thirty years ago, in the very eve of the founding of the Mycological Society of Serbia, a mushroomer who wanted to improve his knowledge using foreign professional literature, the so-called guides for mushroom picking, because, at that time, in Serbia - apart from the publication Nutrition in Nature (1977) with a section on fungi , written by mycologist VojtehLindtner and the book "Mushrooms of Yugoslavia" (1979) written by mycologist Ivan Foht - there were no other mushroom literature. The users of these publications were met with a huge strangeness that sounded abnormal to them, perhaps even stronger - discriminatory. Available foreign guides were given, in the preface, maps of the distribution of certain mushroom species throughout Europe; but, on the borders of the former Yugoslavia, that trail was lost. How is it possible that mushrooms do not cross administrative boundaries, young mushroomers wondered, holding in hands and also in their baskets, numerous examples of different types of fungi that strongly denied this illogical fact. This mystery was quickly solved: on said white spaces there were no, or there was very rarely, mycologists reporting to "Europe and the rest of the world" about species growing in our country. But with the founding of the Mycological Society of Serbia in 1992, with membership of both amateurs and professional mycologists, the negative situation is changing. The Society started performing under the auspices of the Museum of Natural History in Belgrade, which seemed to be very encouraging for Society members.

 

PALEONTOLOGY

Ornaments from the depths

On the beaches of the sea and the ocean, anyone can find a precious souvenir, either a snail's shell or a shell, or some interesting stone. If there are rocks washed by the sea waves near the beach, fossils washed from them can also be found. Lovers of these souvenirs will first decide to collect specimens with beautifully preserved ornaments or colors, unaware that many, even broken, specimens have preserved very tiny animals that occasionally seem like a thin blanket covering them like and are generally known only to paleontologists. To most people, they look like plants or mosses. They are often neglected and used by experts dealing with the taxonomy of larger organisms or their skeletons used for other purposes, such as. natural exhibitions. The visitor also focuses on the larger exhibit for which the label is neatly written. However, if it is necessary to study and reconstruct the conditions that prevailed in an aquatic environment, these gentle and fairy-tale beings with a rather solid skeleton are unavoidable in studies. These are Bryozoa, tiny creatures that exclusively live in seabed colonies.

 

EVOLUTION

The giants, from myth
to scientific evidence

The existence of glacial (glacier) origin material outside the area of today’s glacier distribution has long plagued scientists, and especially the mysterious were the so-called. heretical ("wandering") blocks, often huge pieces of rock that looked completely different from all the rocks around him. It was later determined that the "homeland" of these blocks was miles, even hundreds of miles away from where they were found. Who, when and how brought these stone boulders? At first, legends and superstitions danced around the rocks. The remains of animals from that era fueled the human imagination even more. At the beginning of the 18th century, the interpretation of glacial deposits by "Biblical Flood" prevailed among geologists. It was thought that only such waters could have had sufficient strength to move large quantities of material and deposit them after their withdrawal. The bones found fitted nicely into this "theory" - these were the bones of humans and animals killed in the Flood.
The fact that many Ice Age animals were quite large, and that their bones, well preserved, were shallowly “buried” caused people to encounter them in the earliest periods of history. Thus, the bones of mammoths, runny rhinos, cave bears ... were considered the remains of mythical beings such as giants, unicorns, dragons.

 

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