THE FEATURE ARTICLE OF THIS ISSUE

Physical appearance, behavior, heredity of organism

Genetics is a science which studies genes, heredity and variations between organisms. Performing experiments, geneticists every day discover new ways for studying gene functions, like the analysis of genetic interactions. Within the organism genetic information are located in chromosomes which are expressed by chemical structures like the DNA molecule. Genetics can predict physical appearance of some organism and its plausible behavior. However, factors in the surrounding environment and unpredictable factors upon which we have no influence also play significant role in genetics. For instance, monozygotic twins are clones which are generated by early division of embryo, therefore they have the same DNA molecule, but behave differently and have different fingerprints. /p>

ROCKET TECHNOLOGY

Around mid-20th century Japan witnessed impressive growth of interest for rocket technology, which lead to development of a series of sounding rockets (used for research in higher levels of atmosphere, scientific studies and technologic testing in the nearby space). Yugoslav leadership of the time also became interested for those rockets. A contract for purchasing of sounding rockets „kappa” was signed in December 1960. The rockets were delivered in spring 1962. With assistance of Japanese experts, the rockets were successfully launched by representatives of the Associations of astronautic and rocket organizations of Yugoslavia from the Prevlaka polygon in May 1964. Export of Japanese rocket technology in the early 60s caused suspicion in the USA because of a possibility of its usage for military purposes. The USA expressed concern that, with advanced rocket fuels, Yugoslavia could develop its own large diameter and long range rockets, particularly so because both the blastoff device and the radar delivered for the „kappa” rockets were used for experiments with the antiaircraft rockets „volcano”. Consequently Japan ceased further cooperation with Yugoslavia in this area and in 1967 an official act was passed by which Japan agreed not to export technology which can be used for military purposes to communist countries and countries in conflict with their neighbors.

DENTAL MEDICINE

Modern implantology

Total dental prosthesis are most often applied, and dental implants have, for decades, been the best solution for irretrievably damaged teeth. However, unlike the relatively dysfunctional prosthesis and classical implant therapy, mainly based upon „the more – the better principle, in the course of the last ten years (five years in Europe) – a more economical innovative implant program has been used – known as „All on 4”. Dr. Miloš Jevremović, a post graduate in oral surgery, introduced it in dental medicine practice of the Belgrade-based Bel-Medic. „All-On-4” is the most economical form of stable implant treatment with outstanding esthetic results, which provides the patient a new quality of life and restores the lost selfconfidence, emphasizes Dr. Jevremović. This therapy has been the objective of the two-decade research of Prof. Paulo Malo, and used in practice around the globe for ten years now.

PROBLEMS WITH „IMMORTALITY”

Forgetfulness and anxiety

Nothing is forgotten in our brain, but the brain needs to filter memories and facts which we remember in order to avoid overloading. The question is: what would happen when people could reach several thousand years of age? I they would not remember events older than the last hundred years – the question is what is the meaning of immortality. What will happen to all those information mislaid in the brain? Electronic memory could provide help. We could save our memories and all the data from our brain in external devices and enter them into the brain when needed. Just like we now insert the USB into our computer – we will insert such memory into the brain. But that is not an ideal solution. A portable brain memory can result with abuse. Someone can hack the memory and insert false remembering. Or even worse, someone can access and delete it all!

ELIZA EFFECT

Computer in the role of psychiatrist

One of the constantly repeated promises is that researchers will, in the near future , succeed in developing intelligent machines. It is already widely known that software system do exist which can, on their own, drive a car, play better than Kasparov, communicate with people and design original art pieces. It has been announced, and not only once, that it was merely a question of time when computers would possess intelligence equal to human and that people might be replaced by software in their jobs. Impact of computers on the society is beyond any doubt, risks are also actual and existing, however, how close we really are to creation of artificial intelligence? One of the first programs that enable (textual) conversation in a natural language between a man and a machine was developed between 1964 and 1966. Author of that program, Joseph Weizenbaum, named the program „Eliza”, after the female character in a drama „Pygmalion” who is taught by her tutor to speak properly and have nice manners. In order to place such conversation into some context, Weizenbaum decided to make it simulate a psychotherapist.

ZOOLOGY

Hibernation and winter dormancy

There are many ways animals use to survive unfavorable conditions. Traditionally, depending on stability of their body temperature, animals are divided into homeotherms and poichilotherms. Homeotherms are those that can keep their body temperature stable, no matter what changes occur in the environment, while body temperature of poichilotherms varies and depends on the temperature of their environment. Animals developed various forms of dormancy, that is periods of inactivity when level of their metabolism is decreased. During dormancy animals have reduced need for food, which means that dormancy is an excellent adjustment to winter conditions when food is most often not available. Depending on its duration, dormancy can be divided into five stages: sleep, torpor (numbness), hibernation, winter dormancy and estivation (summer dormancy caused by hot climate conditions).

ENERGY

Solar cookers

One of the areas disregarded by the media is the use solar energy for cooking. It is largely present in southern part of the world and countries with numerous population (China, India, Africa) where conventional fuel (wood, coal, oil, gas…) is lacking but solar rays are abundantly present. A simple definition of a solar cooker would be: a device which uses solar energy for heating and preparation of food. Most solar cookers in use today are relatively low cost devices. Since they don’t use any fuel, that is they operate at no cost at all, many non-for-profit organizations promote their use. Such devices can be produced in a household and in mass, commercial, production. The choice range is large: from small meant for one dish only to the big ones designed to allow preparation of more meals at the same time.

GEOLOGY

Serbia of „once upon a time”

Appearance of our planet in the past did not merely go for location changes of the continents, but also for changes on the surface of the continents. Various processes taking place on the continental soil caused both formation and destruction of previously deposited sediments and previous geologic landscapes. In the course of the major part of geologic past, Serbia was under water. At the bottom of a seas and oceans various sediments were set down forming a multi-layer barriers or massive limestone, conglomerates, sandstones, marls, etc. However, when that soil remained on the surface such sediments could not be deposited, and the previously existing were exposed to erosion and influence of various natural forces which were breaking them up and transporting to some other locations, thus forming the new appearance of the relief.