Sentences with phrase «low oxygen concentrations»

Charcoal is made from wood (or coconut shells), by heating it at very high temperatures (800 to 1,200 degrees) with very low oxygen concentrations.

Researchers demonstrate that the application of low oxygen concentrations may make adipose stem cell - based therapies safer and more effective

If found in rocks having experienced a diagenetic history, these structures could help identify the presence of low oxygen concentrations in ancient iron - rich environments.

Some microaerophilic Fe (II)- oxidizing bacteria produce organo - mineral structures, so - called twisted stalks, in the presence of high iron and low oxygen concentrations.

Mangrove rivulus, which can live out of the water for extended periods of time (days or weeks, as long as the conditions are moist), uses its specialised jumping technique when water has low oxygen concentrations or high levels of hydrogen sulphide, or to escape predators and search for terrestrial prey such as crickets.

Because carotid cells produce so much dopamine — up to 45 times more than the fetal neurons — and because they thrive in the relatively low oxygen concentrations found in the brain, he explains, they may do a better job at correcting Parkinson's symptoms than the fetal cells do — and they raise fewer ethical questions.

Near - freezing water, lack of sunlight, and low oxygen concentrations discourage the growth of bacteria and other organisms that can break down debris.

Instead, species that immigrate from areas with higher water temperatures and lower oxygen concentrations will establish themselves and displace the native polar species,» says Hans - Otto Pörtner.

Previous studies have shown that they have lower oxygen concentrations in the blood of their arteries (ScienceNOW, 16 September 2004).

Mouse fetal development is perturbed by culture in low oxygen concentration that increases expression of oxygen - sensitive genes via hypoxia inducible factors: A non-epigenetic embryonic programming phenomenon?

This is because hydrate decomposition primarily occurs in the Pacific Ocean, where present - day seawater has low oxygen concentration.

Not exact matches

Landon was diagnosed with hypernatremic dehydration (a high concentration of sodium in the blood), cardiac arrest from hypovolemic shock (a condition where the liquid portion of the blood is dangerously low), and hypoxic - ischemic encephalopathy (a brain injury caused by oxygen deprivation).

This expanse of low - oxygen, or hypoxic, waters is produced by an overgrowth of algae caused by high nutrient concentrations.

Another strategy is to make alternative versions of terminal oxidases, enzymes in the membrane that transfer electrons to oxygen, which use oxygen more efficiently or are better at scavenging oxygen when its concentration is low.

Globular clusters contain far lower concentrations of the planet - forming heavy elements — such as carbon, oxygen, and iron — than do our sun and nearby stars, leading some to suspect that it might be difficult for planets to form there.

The animal's greatest advantage seems to lie in the ability of its haemocyanin to take up oxygen from water passing over its gills even when the concentration of oxygen is very low.

In test tube experiments, the researchers found that their haemoglobin - coated particles picked up oxygen when there was a lot around and released it later when the concentration was lower.

«Concentrations of oil in this deep plume are so low that we don't see oxygen depletion,» he explains.

The normal job of the carotid body, nestled in the carotid artery, is to signal your brain to step up your breathing if your blood oxygen concentrations drop too low.

This would include low oxygen subsurface sites with environmental conditions predating the Great Oxidation Event that occurred about 2.3 billion years ago when the atmosphere went from very low to high oxygen concentrations.

The vacuum technology described in your article about chicken slaughter reduces the oxygen concentration to lower levels than required for...

The time required by the electrons to lower their energy level is directly related to the concentration of oxygen in the surrounding air.

In Earth's geological record, the appearance of high concentrations of manganese oxide minerals is an important marker of a major shift in our atmosphere's composition, from relatively low oxygen abundances to the oxygen - rich atmosphere we see today.

By comparison, slightly younger deposits with lower molybdenum and rhenium concentrations had osmium isotope evidence for less continental input, indicating the oxygen in the atmosphere had disappeared.

From yeast to worms to humans, this stress response and its primary regulator, heat shock factor 1 (HSF1), help normal cells adapt to harsh environments, including the presence of heavy metals, high salt concentrations, low oxygen levels, and of course increased temperatures.

Early in the experiment, microbial breakdown of carbohydrates in the additives reduced the oxygen concentration in the water to extremely low levels.

In a laboratory experiment at the Alfred Wegener Institute, ephyra larvae of moon jellies developed perfectly at elevated water temperatures, lower pH values and reduced oxygen concentrations.

Hypoxia, or low oxygen, is an environmental phenomenon where the concentration of dissolved oxygen in the water column decreases to a level that can no longer support living aquatic organisms.

But the boiling point of heavy water, as well as heavy oxygen water (H2O ^ 18 rather than H2O ^ 16) are higher than that of normal water, and are found in water vapor in the atmosphere at lower concentrations when the global temperature is low.

But pollution also covers hundreds of chemicals which are fine or even beneficial at low levels but which if released in large quantities or in problematic circumstances cause «harm» — like phosphorus (grows your veges but also leads to toxic cyanobacterial blooms which kill cattle), nitrogen (grows crops kills many native species of plants and promotes weed growth costing farmers), copper (used as an oxygen carrier by gastropods but in high concentrations kills the life in sediments which feed fish), hormones like oestrogen (essential for regulating bodies but in high concentrations confuse reproductive cycles especially with marine life) or maybe molasses from a sugar mill (good for rum but when dumped into east coast estuaries used to cause oxygen sag in estuaries leading to massive fish kills).

I am starting an oxygen market with the premise that oxygen is destroyed everytime you burn fossil fuels and there may be one day dangerously low levels of oxygen as the CO2 concentration rises.

The worst - case result is that mean ocean oxygen concentration falls to a low of about 68 % of pre-industrial levels in the next few millennia, while low - oxygen «dead zones» — which don't support fish or many other marine animals such as crabs and clams — spread nearly six-fold to cover 12.8 % of the sea surface area.

The paper, «Reconstruction of past atmospheric CO2 concentrations by ice core analysis», acknowledges that, due to impurities, liquid water can exist as low as -50 deg C. Diffusion of CO2 into this water, due to its far higher solubility than nitrogen and oxygen, will partially deplete the CO2 from trapped air bubbles.

Measured decreases in the fraction of other forms of carbon (the isotopes 14C and 13C) and a small decrease in atmospheric oxygen concentration (observations of which have been available since 1990) show that the rise in CO2 is largely from combustion of fossil fuels (which have low 13C fractions and no 14C).