Oxygen deficit

The most recent comprehensive assessment of the quality of rivers in the USA is that of Smith et al. 12), This followed an earlier assessment by Wolman et al. in 1971 (iS). The former 1987 assessment was based on 24 water quality measures from 161-383 stations around the country covering the period 1974-1981. Trends observed included major increases in nitrate, phosphorous, sodium, suspended sediment, fecal bacteria, dissolved oxygen deficit, arsenic and selenium. Major decreases were observed with nitrate, suspended sediment, fecal bacteria, dissolved oxygen deficit and lead. 

Cornett RJ, Rigler FH (1980) The areal hypolimnetic oxygen deficit an empirical test of the model. Limnol Oceanogr 25 672-679... 

Cornett RJ, Rigler FH (1979) Hypolimnion oxygen deficits their prediction and interpretation. Science 205 580-581... 

The rate of reaeration is assumed to be a first order process, which is proportional to the oxygen deficit (i.e., the saturation dissolved oxygen concentration minus the actual dissolved oxygen concentration.) ... 

The dissolved oxygen deficit can be defined as the difference between the actual dissolved oxygen concentration and the saturation concentration for oxygen in the river at the same conditions. 

An anginal pain attack signals a transient hypoxia of the myocardium. As a rule, the oxygen deficit results from inadequate myocardial blood flow due to narrowing of larger coronary arteries. 

The question raised by Anderson (1970,1971) and Anderson et al (1973) as to whether anion point defects are eliminated completely by the creation of extended CS plane defects, is a very important one. This is because anion point defects can be hardly eliminated totally because apart from statistical thermodynamics considerations they must be involved in diffusion process. Oxygen isotope exchange experiments indeed suggest that oxygen diffuses readily by vacancy mechanism. In many oxides it is difficult to compare small anion deficiency with the extent of extended defects and in doped complex oxides there is a very real discrepancy between the area of CS plane present which defines the number of oxygen sites eliminated and the oxygen deficit in the sample (Anderson 1970, Anderson et al 1973). We attempt to address these issues and elucidate the role of anion point defects in oxides in oxidation catalysis (chapter 3). 

Fecal coliform bacteria Fecal Streptococcal bacteria Dissolved oxygen Dissolved-oxygen deficit (DOD)... 

Dissolved Oxygen Deficit (DOD). The sampling station report indicated a net decrease in DOD (thus an improvement in dissolved oxygen conditions). DOD declines were reported in the New England, Mid-Allantic, Ohio, and Mississippi regional basins increases were most frequently found in the Southeast. These data appear to confirm the success of point-source control efforts. Decreases in DOD were found most often (beyond expectations ) where point sources dominated increases... 

Hutchinson, G.E. (1938) On the relation between the oxygen deficit and the productivity and typology of lakes. Inti. Rev. Gesmaten Hydrobiol. 36, 336-355. 

A resonance unique to brain and nerve tissue and believed to be a specific marker for neurons (nerve cells) is V-acetylaspar-tate (NAA), structure 16-6, appearing at 2.0 ppm. NAA often decreases in the damaged brain tissue, suggesting that neurons have died. The damaged brain tissue also contains elevated lactate, structure 16-7, which is an indication that anaerobic metabolism, a pathway forced by oxygen deficit, is taking place. Only the methyl doublet of lactate (1.3 ppm) appears in the spectrum the methine quartet overlaps the water resonance and is normally never observed in vivo. 

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