How to deal with a decompression diving accident
If a diver shows any symptom when he or she goes out to the surface, we will make him lay down on his side, with his head being supported and his higher leg bent at the knee. After that we will give him oxygen. It is important to not block the blood flow and for that reason we will stop him from crossing his legs or resting his head on an arm, for example. If you are eliminating gases still, blocking the circulation of a member could interfere this process.
Flatworms, Marine Biology.
They are characterized for having a head region with sensory organs and neural networks. In this area we find the mouth, used for two things: to ingest food and to excrete the undigested remains, as their digestive system is blind (does not have anus). They do not have respiratory nor circulatory apparatus. The parasitic species have sucker organs to hold on to their hosts. Flatworms locomotion is performed by the activity of their ectodermal epithelium. Their muscles are smooth, similar to snails. They are hermaphroditic, although some species reproduce by parthenogenesis.
The flatworms are a large group of about 10,000 species.
Physics applied to diving
Archimedes’ principle is applied to the diver as a totality. The diver’s body (and his equipment) have a total mass and displace a volume of water which is equivalent to the volume of the immersed body. The diver is subjected to two opposite forces: on the one hand the effect of gravity on the mass (being this one the weight of the diver and his equipment), and on the other hand the buoyant force exerted by the water, equivalent to the mass of water volume displaced by the diver. When the diver’s mass is bigger than the mass of the displaced water volume, buoyancy is negative and the diver sinks. When the diver’s mass is less than the volume equivalent to his mass, buoyancy is positive and the diver floats. The situation where the forces are the same and the mass of the diver is equal to the mass of the water that he displaces, we consider neutral buoyancy: the upward force is offset by the downward force.
Physiology applied to diving
Body components that are attached directly to the backbone (like most of the muscles) keep their position, but the ’free’ components or the ones that are not as much associated with the skeleton (such as the abdominal viscera) maintain their position by balance of forces.
The respiratory system, consisting of bags and ducts, represents organs and tissues where the gas phase is the most important. Blood is the most important tissue of the liquid phase. Finally all the other tissues (muscles and other organs) have the consistency of the flesh: more or less firm and deformable.
Sea Turtles endangered
An amazing feat of sea turtles is their ability to migrate and then return to the same beach to nest.
struggle of turtles for survival, starts when it hatches, because they must travel
on their own from the beach to the sea. The first 48 hours of their life are
critical, since they have to stay safe from the predators and also find their
Poisonous tropical sea fish
Previously, scientists believed that there were only 200 poisonous fish. The new additions double the number to more than 2,000 species of venomous vertebrates.
Operation of the regulator’s first stage
Since the pressure is adjusted twice, the two parts of the regulator that apply the changes have been called "stages".
The first stage receives air from the bottle and set it up to about 10 bars, which can be adjusted according to the manufacturer. The second stage regulates the air flow from the intermediate pressure chamber to the plunger tip. The pressurized air passes from the bottle and a high pressure chamber to an intermediate pressure, and finally to ambient pressure at the depth the diver is. A manometer connected to the high pressure chamber indicates the pressure of the tank. There are two second stages connected to the intermediate chamber: the main nozzle and the octopus. The hose to inflate the jacket or the dry suit connects to this chamber as well.
Deep Stops to Reduced the formation of microbubbles
It has been proven that the microbubbles - also known as silent bubbles - form in divers who perform repetitive dives. They may even form when divers perform a dive within the no-decompression limits.
Diving in cold water. Important considerations
A diving regulator is an automatic device that releases air at ambient pressure when the diver needs it. The air reservoir is compressed in the bottle. The modern filling pressure bottles is between 230 and 300 bars and this pressure must be reduced to ambient pressure by the regulator.