We do not feel the nitrogen of air, and scientists do not believe that under normal pressure nitrogen can affect human organisms. However, being under water or in the altitude chamber nitrogen produces a different effect. Once the pressure is increased about four times, simulating the pressure which exists at the 30- meter depth, the first signs of intoxication usually show up. They are the same that accompany alcoholic intoxication: unreasonable gaiety, talkativeness, depressed attention, impaired self-control. When the diver descends even deeper, he can easily overlook a danger and experiences difficulty in controlling his movements. Being intoxicated the diver may forget where he is and what he is doing, and may even endanger his life. It has been recognized for almost 70 years that it is nitrogen that causes this effect, and the phenomenon itself has been called nitrogen narcosis. In order to avoid nitrogen effect, physiologists have developed mixtures for breathing at sea depths. In these mixtures relatively inexpensive nitrogen have been replaced by very expensive helium.
Nevertheless, that did not solve all the problems. Nitrogen narcosis effects may even occur with regular dives at depths of 30-40 meters, where helium is not used in the majority of cases. Therefore, it was required to develop a method which would increase the level if resistance to nitrogen narcosis effects. Such method is under way in the Sechenov Institute of Evolutionary Physiology and Biochemistry, St. Petersburg, under the guidance of Alexander Vjotosh. The researchers exposed laboratory rats to higher temperatures or kept them in the air with insufficient oxygen content, and the rats became more resistant to the nitrogen narcosis effects – they managed to pass appropriate tests with better results. After a special training course the resistance increased about one and a half times. If divers were to take this training course, they would be exposed to a lesser risk working underwater. The rats’ resistance to nitrogen narcosis was also one and a half times raised due to quercetin action in cases when they had been injected the substance eight hours before the diving.
The researchers from St. Petersburg have come forward with a new hypothesis explaining the nitrogen action under pressure. The generally adopted point of view is that nitrogen dissolves in cells’ membranes, causing the change of their characteristics, thus violating nerve impulses formation or conduct. The physiologists from the Sechenov Institute have assumed that under the nitrogen increased pressure in the organisms there are formed additional portions of the active compound, which damages cell proteins.
Sergey Komarov | Informnauka
Investigators may unlock mystery of how staph cells dodge the body's immune system
22.09.2017 | Cedars-Sinai Medical Center
Monitoring the heart's mitochondria to predict cardiac arrest?
21.09.2017 | Boston Children's Hospital
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
22.09.2017 | Life Sciences
22.09.2017 | Medical Engineering
22.09.2017 | Physics and Astronomy