Assimilation number

However, as pointed out by Sathyendranath and Platt (1994) and Sathyen-dranath etal. (1999), models that only consider mixed layer dynamics without taking into account changes in bio-optical properties of phytoplankton are probably insufficient to explain the occurrence of phytoplankton blooms in the Arabian Sea. Sathyendranath etal. (1999) provided evidence for significant seasonal changes in the parameters that describe the dependence of photosynthesis rate of phytoplankton on the amount of light available (P-I curves), viz. the assimilation number (PmB) and the initial slope of photosynthesis-light curve (aB), as well as in the specific absorption coefficient of phytoplankton (ac ). 

R being the relative photosynthesis, determined empirically, for the appropriate value of surface radiation, k the extinction coefficient per metre of the water, C the amount of chlorophyll in g m, and the factor 3.7 a mean value for the assimilation number. Values estimated by this method and those determined by the oxygen technique agreed reasonably well for a number of sea areas in which primary productivity varied by an order of magnitude (Fogg, 1975). 

Sometimes pollution is acceptable in small amounts. When Columbus landed in the New World there were an estimated 15,000 Indians living in the area that is now Ohio (1970 population 10,652,017). Did these Indians pollute the environment They made open tires, something that is now banned in all municipal areas, and they urinated and defecated at large. Still, since they were so few in number, the cleansing actions of the air, water and biosphere could rapidly assimilate then-wastes and no accumulating harm was done. In the strict sense of the word pollution, they did dirty the streams and anyone drinking the water shortly afterwards could contract the diseases whose infective agents were present in their wastes. However, with a little care this was unlikely, and their pollution was not considered bad. 

A variety of commercial kits and automated systems are available to test the abilities of bacteria to assimilate, ferment, decarboxylate, or cleave selected organic compounds.46 Their reliability for species identification is usually greater with cultures from clinical samples, where a limited number of bacteria are commonly encountered, and less with environmental soil and water samples, where a great many uncommon or previously unidentified species not in the database are likely to be present.29,45 Additional tests beyond those found in the commercial kits may be necessary for example, the hydrolysis of various nitriles and amides is useful for identifying Rhodococcus spp.47 Some commercial kits for clinical use feature antimicrobial susceptibility testing.21... 

Although the adjustment of model phytoplankton concentrations takes places every month, not all shallow water locations are affected by it every month. Since MERIS is an optical sensor, light availability limits its ability to measure ocean colour. Hence solar angle and clouds determine, whether assimilation is possible or not. The number of months in which is assimilation is possible is higher for locations close to the equator than locations at higher latitudes (Figure 2. lb)). 

Fig. 2.1 a) Ocean waters with water depth lower than 250 m b) Total number of month per year in which MERIS data assimilation takes place. 

One of the most popular bioassay for interferons is termed the cytopathic effect inhibition assay . This assay is based upon the ability of many interferons to render animal cells resistant to viral attack. It entails incubation of the interferon preparation with cells sensitive to destruction by a specific virus. That virus is then subsequently added, and the percentage of cells that survive thereafter is proportional to the levels of interferon present in the assay sample. Viable cells can assimilate certain dyes, such as neutral red. Addition of the dye followed by spectrophotometric quantitation of the amount of dye assimilated can thus be used to quantitate percentage cell survival. This type of assay can be scaled down to run in a single well of a microtitre plate. This facilitates automated assay of large numbers of samples with relative ease. 

The acquisition and assimilation of bioelements are the most fundamental processes in an organism s struggle for life. It is therefore obvious that in complex natural systems the competition between thousands of species for limited quantities of a small number of elements is a major evolutionary factor. However, the individual contributions of the physical and biochemical aspects of nutrition to the fitness of an organism are widely unknown. The frequent observation that biodegradation processes, e.g. in soil remediation, are limited by physical obstacles to substrate acquisition, rather than by biochemical incapacities, points at the importance of substrate mobilisation strategies. 

Racially the American people, if they are to remain American, are to purge their existing family stocks of degeneracy, and are to encourage a high rate of reproduction by the best-endowed portions of their population, can successfully assimilate in the future many thousands of Northwestern European immigrants. . . But we can assimilate only a small fraction of this number of other white races and of the colored races practically none. 

The fungus assimilated various polyesters. In general, assimilation of aliphatic polyesters by the fungus was better the greater the number of carbon atoms between the ester bonds. Polyesters with side chains were generally less assimilated than without side chains. The fungus also assimilated unsaturated aliphatic polyesters, but hardly assimilated alicyclic and aromatic polyesters. 

There are broadly two uses of chemometrics that interest the process chemist. The first of these is simply data display. It is a truism that the human eye is the best analytical tool, and by displaying multivariate data in a way that can be easily assimilated by eye a number of diagnostic assessments can be made of the state of health of a process, or of reasons for its failure [ 153], a process known as MSPC [154—156]. The key concept in MSPC is the acknowledgement that variability in process quality can arise not just by variation in single process parameters such as temperature, but by subtle combinations of process parameters. This source of product variability would be missed by simple control charts for the individual process parameters. This is also the concept behind the use of experimental design during process development in order to identify such variability in the minimum number of experiments. 

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