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Oxygen toxicity is a condition resulting from the harmful effects of breathing molecular oxygen (O 2) at increased partial pressures.Severe cases can result in cell damage and death, with effects most often seen in the central nervous system, lungs, and eyes.
The study was based on data obtained from May 1914 to April 1915 by the United States Public Health Service under supervision of Surg. W.H. Frost. [ 1 ] More complex versions of the Streeter–Phelps model were introduced during the 1960s, where computers made it possible to include further contributions to the oxygen development in streams.
5-million-year history, representing the Lisiecki and Raymo (2005) LR04 Benthic Stack Sections of sedimentary cores from off Greenland. Marine isotope stages (MIS), marine oxygen-isotope stages, or oxygen isotope stages (OIS), are alternating warm and cool periods in the Earth's paleoclimate, deduced from oxygen isotope data derived from deep sea core samples.
The best known explanation of the oxygen effect is the oxygen fixation hypothesis developed by Alexander in 1962, [9] which posited that radiation-induced non-restorable or "fixed" nuclear DNA lesions are lethal to cells in the presence of diatomic oxygen. [10] [11] Recent hypotheses include one based on oxygen-enhanced damage from first ...
Global meteoric water line. Data are global annual average 18 O and 2 H values from precipitation monitored at IAEA network stations distributed globally (n=420). [1]The Global Meteoric Water Line (GMWL) describes the global annual average relationship between hydrogen and oxygen isotope (oxygen-18 [18 O] and deuterium [2 H]) ratios in natural meteoric waters.
Pressurized aircraft cabins are typically maintained at 75 kPa, the pressure found at 2,500 m (8,200 ft) altitude, resulting in an oxygen partial pressure of about 16 kPa, which is the same as a 15% oxygen concentration in a hypoxic-air application at sea-level pressure. However, passengers are sedentary and crew members have immediate access ...
Pacific Ocean sections of dissolved oxygen and apparent oxygen utilization. Data from the World Ocean Atlas 2009 . In freshwater or marine systems apparent oxygen utilization ( AOU ) is the difference between oxygen gas solubility (i.e. the concentration at saturation) and the measured oxygen concentration in water with the same physical and ...
[13] [53] [2] [54] [55] However, oxygen remained scarce in the atmosphere until around 2.0 Ga, [14] and banded iron formation continued to be deposited until around 1.85 Ga. [13] Given the rapid multiplication rate of cyanobacteria under ideal conditions, an explanation is needed for the delay of at least 400 million years between the evolution ...