Nutrient data analysis

Anderson, L. A. and Sarmiento, J. L. (1994). Redfield ratios of remineralization by nutrient data analysis. Glob. Biogeochem. Cycles 8,65-80. 

Anderson L. and Sarmiento J. (1994) Redheld ratios of remineraUzation determined by nutrient data analysis. Global Biogeochem. Cycles 8, 65—80. 

D. Biochemical Systems Theory and Nutrient-Response Analysis of Data on Three Dietary Proteins Conclusions... 

Efforts were also made to evaluate whether the supplementary intake of nutrients included in the MeD could also be a health-protective policy. The most effective trial in establishing such information was the GISSl-Prevenzione trial which was focused on fish-derived n-3 fatty acids supplementation. The trial was conducted on 11,324 patients who had a first acute coronary syndrome and followed for a period of 3.5 years. The patients were randomly stratified in four groups the first receiving 1 g of n-3 fatty acids per day the second a supplement of 300 mg vitamin E per day the third both supplements and the fourth only dietary guidelines. The data analysis revealed that the first group receiving only 1 g n-3 fatty acids supplementary had a lower risk of secondary CVD. 

Bioprocess Control An industrial fermenter is a fairly sophisticated device with control of temperature, aeration rate, and perhaps pH, concentration of dissolved oxygen, or some nutrient concentration. There has been a strong trend to automated data collection and analysis. Analog control is stiU very common, but when a computer is available for on-line data collec tion, it makes sense to use it for control as well. More elaborate measurements are performed with research bioreactors, but each new electrode or assay adds more work, additional costs, and potential headaches. Most of the functional relationships in biotechnology are nonlinear, but this may not hinder control when bioprocess operate over a narrow range of conditions. Furthermore, process control is far advanced beyond the days when the main tools for designing control systems were intended for linear systems. 

Fig. 1 Results from a redundancy analysis of stream nutrient concentrations vs. catchment characteristics in 31 headwater catchments in Catalonia (Spain). Note how phosphorus (SRP) and ammonium (NH4) appear associated with urban point and diffuse sources (Urban percent urban land use, Inhabs number of inhabitants, eq. inhab inhabitant equivalents), whereas nitrate (NO3) concentration is positively associated with irrigated agriculture (IrrAg) and bovine cattle units (ECU), and negatively with mean catchment slope (slope) and percent forest land (Forest). The other variables are Area log area, P precipitation, NonIrrAg non irrigated agriculture. Data are from the Catalan water agency (http //ww.gencat.cat/ac)...

Much of the analytical data on the nutrient content of foods is generated using official methods of analysis (e.g. AO AC International). An evaluation of AO AC Methods of Analysis for Nutritional Labelling is available (Sullivan and Carpenter 1993). While these methods have often been studied for a variety of food matrices, applicability over the entire range of food matrices has not been formally studied in most cases. In addition, RMs are not available over the entire range of food matrices (Wolf... 

The duration of acclimation is affected by several environmental factors, such as temperature, pH, aeration status, and nutrients. The concentration of the compound that is being metabolized greatly affects the length of time before a decline in its concentration is detectable. The rate of biodegradation of trace compounds increases with concentration, but because compound loss is usually determined and not C02 or product formation, the low precision of analysis leads to data indicating a longer acclimation at higher concentration [104,106,113,128]. 

The investigation of body fluids with respect to nutrient (essential) elements and toxic elements -which are challenging topics for analytical chemistry - include the determination of concentrations at the trace and ultratrace level. However, isotope variation and isotope effects (especially of lighter elements such as hydrogen, carbon, nitrogen, oxygen but also of iron and calcium) have also been studied.22 23 The most frequently applied mass spectrometric technique for the analysis of body fluids today, which fulfils all requirements and also results in accurate and precise data, is ICP-MS. 

We have investigated the humification of straw, as an example, under constant conditions of humidity and temperature in a climatic chamber (4,18) and separated different fractions according to a modified method of Waksman s proximate analysis. The amount of nitrogen present in these processes is the factor limiting the rate of decomposition. Therefore we added nitrogen in form of ammonium nitrate in a quantity of 1% of straw dry weight to a nutrient solution in one experiment while the nutrient solution had no nitrogen in a parallel experiment. Table I shows the calculated data. 

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