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Mechanisms of addiction development

Addiction is a robust, acquired need to use a psychoactive substance or perform an activity. A person with an addiction uses a substance or engages in behavior whose rewarding effects provide an irresistible incentive to repeat the activity, despite the harmful consequences. Addiction can include the use of substances such as alcohol, inhalants, opioids, cocaine, and nicotine, or behaviors such as gambling, shopping, playing computer games, eating, or having sex.

History

The origins of mass spectrometry

Mass spectrometry is a technique used to analyze the chemical composition of a sample. It uses ionizing radiation to separate the molecules of the sample into their constituent ions, which are then separated according to their mass-to-charge ratio. Mass spectrometry has been used since the early 19th century, but the principles behind it have been known about 100 year earlier.

Biology Microbiology

Characteristics of Escherichia coli

Escherichia coli was discovered in 1885 by Theodor Escherich, an Austrian pediatrician, who isolated the bacterium from stool samples of newborn babies. It belongs to the family Enterobacteriaceae, comprising about 60 genera with more than 200 different species

Why is water so important for living organisms?

Biology

Why is water so important to living organisms?

Water, although it is a very simple molecule, because it consists of only 3 atoms - one oxygen and two hydrogen - is the foundation of life on Earth, and probably in the universe at all (if we find one). It is not without reason that when observing distant solar systems, astronomers look for planets that are in the so-called habitable zone, i.e. the habitable zone enabling, among others, the occurrence of liquid water. But let's go back to Earth and look at water from the side of its properties important for life ...

Laboratory

Baume scale

The Baume scale (Be scale) is the density scale of the liquid solution.

Astronomy Astrophotography

NGC 891

NGC 891, is a spiral galaxy about 30 million light years away from Earth. Its diameter is estimated at 100,000 ly. We can observe it in the constellation of Andromeda...

AT WHAT TEMPERATURE DOES AN ETHANOL SOLUTION FREEZE

Chemistry Laboratory

What is the freezing point of ethanol?

Pure ethanol freezes at about -114 °C. However, by adding more and more water to this alcohol, the freezing point of such a solution begins to approach 0 °C. For example, vodka, a 40% solution of ethanol and water, freezes at -23 °C.

Astronomy Astrophotography

The Horsehead Nebula

The Horsehead Nebula (also labelled Barnard 33), is a dense cloud of dust and ionized hydrogen of 3.5 light years diameter and it's about 1500 light years away. Nebula is…

First ever photo of a supernova. Credit: Victor Buso

History

First-ever photo of a supernova from the very beginning

On the 20th of September 2017, amateur astronomer Victor Buso accidentally took the first-ever photo of a supernova flash at the very beginning of an explosion of this type.

Chemistry

How ammonium nitrate decomposes?

Ammonium nitrate NH4NO3 decomposes in an exothermic reaction and produce two gaseous products from solid reactant: \( NH_{4}NO_{3} _{(solid)} \rightarrow N_{2}O_{(gas)} + 2H_{2}O_{(gas)} \) Enthalpy change is \( \Delta H…

Biology Cell biology

What is cytoplasm?

It has a seemingly simple and uniform structure, fills the entire cell except the nucleus, helping to stabilize it. It can also take on both liquid and gel form. It is the site of many important chemical reactions in the cell, such as protein synthesis, as well as the first phase of breathing. It helps to transport everything that is needed inside the cell. This is how the cytoplasm can be briefly described.