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» Glavni naslovi





Sleeping and dreaming

Human sleep is characterized by the existence of sleeping stages (superficial and deep or NREM sleep) and dreaming stages (or REM sleep). There are three stages of NREM sleep, each of which can last for 5-15 minutes. Before entering the dream stage or REM sleep, a person goes through all three stages of sleep. Stage 1 (or drowsiness) lasts 5-10 minutes, is characterized by closed eyes, but the person is easily awaken. Stage 2 (or superficial sleep) is characterized by slowing down of heart rate and lowering of body temperature. The body is prepared for stage 3 (or deep sleep). A person is quite difficult awakened and if awakened remains for a short while or even few minutes confused and disoriented. During deep sleep, a whole series of processes take place (eg, immune system strengthening). Over the years, sleeping is more and more in superficial stages, and the amount of deep sleep decreases. Aging is associated with shorter sleep, which is compensated by occasional sleeping episodes over the course of the day. Studies, however, show that the total amount of sleep needed for older people is the same as when they were young. Still, what happens in a person during sleep?



Elon Musk cosmic path

The main innovator in cosmic engineering in the world is the "Space X" company. Its main owner and founder, Elon Musk, is not only a businessman, but also a visionary who brings to reality what until recently was just a science fiction. He personally supports the vision of settling the solar system (primarily Mars). "Falcon 9" rockets produced by this company are the first in the history of astronautics to have first degree of retroactive braking and soft, verticall landing, alowing them to be used again.
While other companies in the United States have continuously increased the cost of launching in orbit by mass of cargo, "Space X" is aiming to reduce it. Despite certain difficulties, this company completes the development of a cosmic capsule for the astronaut "dragon 2" capable of performing all kinds of commercial launches to the Earth's orbit, as well as the one towards the Moon and the interplanetary paths. This year, the company continues to make a successful progress with the launch of the "Dragon 2" capsule and another, this time commercial, by launching the falcon 9 heavy rocket. Although part of the cost was covered by NASA ($ 2.6 billion for "Dragon 2"), the initiative for these projects originated from the company and its founder.



Horrible robots

Hiroshi Ishiguro, Japanese a robot engineer and professor at the University of Osaka, conducted in 2002 experiment in which he presented his five-year-old daughter Risa with her robotic duplicate. The girl was abstained from the beginning of the experiment, and after a few minutes with the robot and being occasionally encouraged by her father to interact with robot, she became anxious and just burst into tears that ended the first recorded meeting of a human and modern android.
Risa's negative reaction was not completely unexpected. The insecurity and anxiety that occurs in relations alive - not alive and human -the automated was a common topic in literature and art, but gained a specific scientific importance at the beginning of the 20th century, with Freud defining it as part of a broader psychoanalytical concept. This concept, best known under its original and hard to translate German term "das Unheimliche", refers, inter alia, to the discomfort felt in encountering something we perceive as strange and hostile, while at the same time it reminds us of ourselves. This feeling can be experienced in encounter with corpses, wax figures, prosthetic hands and, presumably, realistic humanoid robots.



Renewable sources 100%

Is it possible today to achieve 100% share of renewable resources on a global scale, i.e. stop using fossil fuels? The shortest answer might be: yes. The next question could be: under what conditions? The precondition is that multiple RES are combined and used together wherever possible. According to data from 2016, RES part in global energy needs is 19.2%. In electricity production, a total of 23.7% are investments nearing 300 billion dollars annually and with the tendency of further growth. At the national level, already 30 countries cover their energy needs from RES by 20%. Iceland and Norway cover RES from 100% and Denmark with 42%, predominantly from wind parks.



From three to two dimensions?

At the end of March, the Foundation Marko Jarić awarded the Physics Prize in the Serbian Academy of Sciences and Arts for the eighth time. The winner of the Serbian Nobel in physics for the year 2018 is professor of the University of Cambridge, Dr Zoran Hadžibabić, who was awarded for extremely significant contributions in the field of physics of ultra-cold atomic and molecular systems. Foundation 'Prof. Dr. Marko Jarić, founded in 1998 by family and colleagues of Dr. Marko Jarić, a world-renowned researcher in the field of physics of condensed matter and professor at the Texas A ! M University, stablished this high recognition which is awarded for exceptional achievements of physicists from Serbia and the diaspora, whose work is internationally recognized. The Institute of Physics from Belgrade, as the first institute of national importance, become a guarantor of the Foundation's long-term financial sustainability, to which it has contributed over the years as one of the founders.



Treatment of allergic sneezing as prevention of asthma

Allergic sneezing (rhinitis), allergic bronchial asthma, children's eczema or atopic dermatitis in adults, are three allergic inflammatory diseases that usually go together - in some cases they can precede each other and sometimes occur in combinations. Usually subjected are people born with a genetic predisposition to allergic reactions and so far it can not be determined wether they can be cured, but they can certainly be treated and controlled in ways that almost bring no harm in normal life and work. The precondition for this is - as emphasized by prof. Dr Mirjana Bogić, an allergist from Belgrade General Hospital Bel Medic - timely recognition.For example, allergic sneezing is a risk factor for the development of allergic bronchial asthma, therefore is of the utter importance that in childhood, when it usually occurs, is not wrongly treated as a "common cold", "bacterial infection" or "middle ear inflammation". Prof . Bogic points out that timely recognition and proper treatment of allergic sneezing is actually a key factor in prevention and preservation the quality of life for people with atopic diseases, which have been worldwide more and more frequent in the last decades.Allergic sneezing (allergic rhinitis) is the most common chronic non-infectious disease of today, affecting about 400 to 500 million people worldwide, both children and adults. Moreover, its incidence is steadily and rapidly increasing , and it is quite justifiable to talk about an epidemic of allergic disease in the world. As an illustration, prof. Bogic cites a recent Italian study in a pediatric sample that concludes that, with the continuing trend of growth, in two years every other child in Italy will have an allergic rhinitis.



Minimally Invasive Chest Surgery

Video-assisted thoracoscopic surgery saves patients from many problems of conventional chest surgery. It is used not only in therapy but in the diagnosis of lung cancer. Doc. Dr Nebojša Marić, head of the VMA chest Surgery Department and Bel Medic associate, points out that further patient treatment can be changed i.e. surgsystemic therapy can be changed only seven days after operation provided patient tumor was diagnosed and surgically removed by VATS. Minimally invasive surgical procedures are a modern trend that marks all surgical branches in medicine. This also includes Video Assisted Thoracoscopic Surgery (VATS) used in the diagnosis and treatment of pathological conditions in the chest cavity (pulmonary diseases, cardiac diseases, esophagus diseases ...). In the same way that laparoscopic techniques reduce the need for large abdominal surgical cuts, VATS eliminates the need for conventional thoracotomy (opening of the chest), which implies the spread of the ribs.Although the basic principles used in open thoracic surgery apply to VATS, in this minimally invasive thoracic procedure, the hands of the surgeon remain outside the chest cavity; because technological improvements made it possible to manipulate surgical instruments inside the chest with the help of an associated video camera, through only one small cut, which significantly reduces the trauma and recovery time of the patient. After two to three days after such surgery, the patient can leave the hospital.



Problematic fossils

Paleontological research can provide an incredible amount of information about the lives of extinct organisms, sometimes as specific as: the precise depth at which the marine organism lived, who were his enemies, how looked part of his body which was not preserved in fossil form, how he "behaved" during his lifetime, and even what he had consumed as his last meal. All data are in the service of taxonomic classification and accommodation of organisms to the tree of life. However, there are some fossils that can not be classified because they do not resemble any known living form. Sometimes they ay resemble some well-known organisms, but were found in least expected places or rocks, and only palaeontologists know why they did not even identify them, nor did they find for them a place in the tree of life.
Non-classified organisms are given the Latin name "Incertae sedis", which refers to taxonomic groups with an insecure position. They are often referred to as enigmatic units or strange taxa, and in fact they represent the problem that scientists will deal with in the future. There is a special vocabulary used to describe organisms that "oppose" the classification and the nomenclature system, and are generally grouped as "problem".


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