The absorption and retention of
47
Ca and
85
Sr have been compared for four volunteers on a normal diet with and without a supplement of sodium alginate. The alginate was given for 7 days in amounts ...approximately chemically equivalent to the dietary calcium.
Alginate decreased the retention of
85
Sr and
47
Ca by about 70 per cent and 7 per cent respectively.
The mean ratio for the absorption of
85
Sr on the supplemented to that on the unsupplemented diet was 0·23. This ratio was greater than that derived from earlier results for subjects given alginate in milk alone.
The urinary and faecal excretion as well as the plasma concentration of stable sodium, potassium, magnesium, calcium, strontium, barium and phosphorus, were measured.
Fertilizer samples are tested for determining their nutrient contents; however, different methods give varying results. Therefore, the major objective of this study was to develop and validate ...potassium determination method by flame photometry technique.
Flame photometry technique for the quantification of potassium concentration in fertilizer samples was validated in Soil and Water Testing Laboratory (ISO/IEC: 17025), Dera Ghazi Khan. The method validation was done for repeatability, reproducibility, limit of detection, limit of quantification, linearity, recovery, selectivity, and bias.
The limits of detection and quantification were 0.87% and 2.88% K2O, respectively. The repeatability was 0.33%, and reproducibility (T-calculated was 0.69 which was less than T-tabulated, i.e., 2.06). Linear curve was obtained for concentrations ranging from 5 to 25 ppm (K) exhibiting R2 of 0.99. The recovery for K in fertilizer sample was 98.8%. The potassium contents were identified with complete recovery without interference of other nutrients in the sample. The Z-score of all the results (Magruder USA, Fertilizer sample check program) were in acceptable range. The correlation coefficient (0.999%) depicts strong relationship between actual K value and observed values.
By this relation, we can say that method performance was excellent. Hence, the method can be successfully used for potassium determination in fertilizer samples.
Chickpea ('Cicer arietinum' L.) is the third most important food legume grown in the world and a favourite food crop in Morocco. Morocco is a semi-arid country with limited fresh water resources. In ...order to meet the food demand, increasing attention is being given to the use of non-conventional water resources such as saline/brackish water and treated waste water for irrigation. With this in mind, an experiment was conducted in the south of Morocco to investigate the effect of irrigation with saline water on a local variety of chickpea. Irrigation with water of different salinity levels was carried out on pot experiments. Differences in water uptake and plant growth; as well as proline, soluble sugar, and Na+ and K+ contents of the plant were quantified. The results showed a negative relationship between increasing water salinity and most of the measured plant growth parameters. Irrigation water salinity has negatively affected growth and biomass accumulation and led to reduced grain yield, water uptake and water productivity. In contrast, proline, soluble sugars, Na+ and Na+: K+ ratio increased with increasing irrigation water salinity. The findings highlighted the role of proline and soluble sugars as osmolytes produced by chickpea to mitigate the effect of salinity stress. The added value of these results is that the crop's responses to salinity are quantified. The obtained values can be used to determine 'threshold values'; should the salinity of the irrigation water go above these threshold values one may expect the crop yield parameters to be affected. The quantified responses also indicate the rate of change of yield parameters in response to the irrigation water salinity level. This could help in avoiding significant yield reduction when deciding on the irrigation water salinity level to be used for the studied chickpea variety.
The work was carried out during the years 2007 and 2008, in a sandy soil located in the experimental field of the Agronomy Department, Universidad Nacional del Sur. The objectives of the work were to ...study the effect of three organic fertilizations on garlic production and to determine the macronutrient content in leaves during the crop cycle. The experiment was carried out in a completely randomized design with four replicates. The treatments were: T0, with inorganic fertilization (100 kg ha-1 of diamonic phosphate + 100 kg ha-1 of urea); T1, 16.07 kg ha-1 of bovine manure-Onion compost (+ 50 kg ha-1 of phosphate rock); T2, 2000 kg ha-1 of BioOrganutsa Nitro Plus a commercial organic fertilizer, (+ 50 kg ha-1 of phosphate rock); and T3, BioOrganutsa Nitro Plus + vermicompost tea (same as T2 + 1,25 L vermicompost tea). During both years, the number of leaves, height and dry weight along the cycle increased in all treatments. T2 and T3 showed the highest values compared to T1. Nitrogen and potassium content in leaves decreased gradually in all treatments after the beginning of bulb formation. At harvest, T2 and T3 presented the highest yield, weight and diameter bulbs in 2008, while T1 obtained the lowest values of these parameters. In 2007 T3 showed significant differences compared to T1 as regards the 3 parameters. The commercial organic fertilizer BioOrganutsa Nitro Plus + phosphate rock, incorporated alone or in combination with vermicompost tea, can be an alternative to fertilize organic garlic crop. It will be necessary to try different doses of the compost to evaluate its value as an organic fertilizer.
To assist the high quality sugarcane production, the practice of individual farm management was investigated using a geographic information system (GIS) with the data of both from the quality-based ...payment system and the near-infrared spectroscopy (NIR). In 2000/01 and 2001/02, the data such as cropping type, potassium content, and unit yield from all fields in Minami-Daito Island were mapped and analyzed to understand the geographical distribution of the crop. Moreover, annual standardization of data including unit yield, sugar content, and potassium content, which reduces the influence of weather, led to better evaluation of each field characteristics. An increase in potassium content was also observed. The system presented can be utilized in improvement of fertilizer management.
Though the mechanism of 201Tl accumulation in thyroid tumours is not known yet, there are some hypotheses. In order to study the mechanism, potassium contents and Na, K-ATPase, of various organs of ...rats and human thyroid glands were analized. The conclusion through these experiments is as follows, (1) as the potassium contents and Na, K-ATPase activity of thyroid glands are not obviously higher than those of other organs, the 201Tl accumulation in thyroid is thought to be not owing to the similarity to the potassium ion, (2) pointing out high activity of Na, K-ATPase in heart and kidney, the accumulation mechanism of 201Tl in these organs has high relation to this activity, (3) though there is a tendency to have higher potassium contents among thyroid tumours, the difference in potassium contents between their histopathology is small; so that the tumour specificity is not explained from the potassium contents, and (4) as for Na, K-ATPase activity of thyroid tumours, papillary adenocarcinoma and follicular adenoma, which take more in 201Tl, have tendency to show higher activity; adenomatous goitre, which take less in 201Tl, has tendency to show lower activity. We suggested that the factor relating to the accumulation mechanism of 201Tl may be multiple, and Na, K-ATPase plays an important role in 201Tl specific uptake in thyroid tumours.
The alterations in the water, sodium (Na) and potassium (K) contents of the frontoparietal cortex, hippocampus and thalamus as well as the protein permeability of the blood-brain barrier were ...investigated in rats 4 h after systemic kainic acid administration. Increases in the water and Na contents and a decrease in the K content were observed together with Evans blue extravasation in the thalamus area indicating the development of vasogenic brain edema. Changes observed in the ion contents of the frontoparietal cortex and hippocampus may be due to a general cell membrane permeability damage but are not caused by a primary disturbance of the blood-brain barrier.
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