Derterminatin of the mineralization coefficient of soil organic nitrogen on two soils at Katherine, NT

1967 ◽  
Vol 7 (26) ◽  
pp. 266 ◽  
Author(s):  
R Wetselaar
Keyword(s):  
Organic Nitrogen ◽  
Nitrate Nitrogen ◽  
Cropping System ◽  
First Year ◽  
Soil Organic Nitrogen ◽  
Legume Crop ◽  
Decomposition Constant ◽  
Nitrogen Yields ◽  
The Mean

The mineralization coefficient (M.C.) (the amount of nitrate nitrogen formed in one season in sift, by bare fallowing the soil, as a percentage of the amount of organic nitrogen in the topsoil at the onset of the season) was measured on two soils at Katherine, N.T. The determination of M.C. is regarded as useful in evaluating the 'true' decomposition constant of a soil under annual cropping conditions. Its relation to the 'apparent' decomposition constant is discussed. Tippera clay loam had a mean M.C. of 4.80 per cent, and the fluctuations around the mean were positively related to amount of rainfall. The M.C. for Blain sand dropped from 12.5 per cent in the first year of cultivation to 5.0 per cent in the third and fourth years. The data indicate that the initial high nitrogen yields on the sandy soil will in time decline to a low level unless a legume crop is incorporated in the cropping system.

scholarly journals Hipparcos, Three Years After Launch

1993 ◽  
Vol 156 ◽  
pp. 1-10
Author(s):  
J. Kovalevsky ◽  
M. Froeschlé
Keyword(s):  
Standard Error ◽  
Present Status ◽  
Double Star ◽  
New Method ◽  
Standard Errors ◽  
First Year ◽  
Mass Determination ◽  
Mission Duration ◽  
The Mean

In a first part, the present status of the HIPPARCOS mission is described. Despite the degradations and failures of gyroscopes, it is still hoped that a 4 1/2 mission duration will be reached. The first-year of data has been reduced by both FAST and NDAC consortia. For the best 46200 observed stars, the distribution of standard errors in positions has a maximum of 1.5 mas in latitude and 1.8 mas in longitude and the mean standard error for parallaxes is of the order of 3 mas. The comparison of results obtained by both consortia shows that the differences are small and quite consistent with the announced internal precisions. Magnitude measurements are precise to 0.02 magnitude for a 4 second observation. The precision to be expected for double star observations is also given. The main new result is that the magnitudes of the components are obtained with a few hundredths of a magnitude precision. This allows to devise a new method of mass determination based upon the parallax and a recalibrated mass-luminosity diagram. The parallax dependence of the results is much more favourable than in the case of the classical determination of masses using orbital motions.

Development of Sacral Ratio Percentile Card for Children: A Preliminary Report

2021 ◽  
Author(s):  
Kutay Bahadir ◽  
Bilgesu Arikan-Ergun ◽  
Atilla Halil Elhan ◽  
Ergun Ergun ◽  
Tanju Aktug
Keyword(s):  
Anorectal Malformations ◽  
First Year ◽  
Clinical Value ◽  
Monthly Basis ◽  
Clinical Evaluations ◽  
Direct Radiography ◽  
The Mean ◽  
First Year Of Life ◽  
Age Independent

Abstract Introduction Sacrospinal anomalies that may accompany anorectal malformations may cause fecal and urinary incontinence despite proper anomaly treatment. The sacral ratio has been suggested in the determination of both the prognosis in terms of incontinence and the need for further examination for sacrospinal anomalies. The normal and clinically decisive values of sacral ratio are given differently in publications. We aimed to determine the distribution of the sacral ratio in children under 12 months and to develop the sacral ratio percentile card that will enable one to give an age-independent parametric result in clinical evaluations. Materials and Methods The files of patients under 1 year of age who had anteroposterior direct radiography including pelvis were reviewed retrospectively. Sacral ratio was studied for 360 patients, 30 patients per month. Percentile card was developed with LMS software and reference values were used as 1, 2, 3, 4, and 10%. Results The lowest sacral ratio value was 0.514 and the highest value was 0.936. There was no statistical difference between the mean sacral ratio of the cases when they were classified on a monthly basis (p = 0.191). Low percentile values were found slightly different at first 4 months of age. Conclusion Although the mean of sacral ratio does not change significantly during the first year of life, values that are considered pathological for patients are within different percentile limits depending on age. Instead of using sacral ratio with some clinically decisive values, we think that parametric evaluation with the help of the percentile card will increase its clinical value.

Determination of forest soil organic nitrogen determination using technique of X-ray absorption near-edge structure

2006 ◽  
Vol 17 (3) ◽  
pp. 189-192 ◽  
Author(s):  
Shun-yao Zhuang ◽  
Meng-jie Xu ◽  
Zheng-yi Hu
Keyword(s):  
Forest Soil ◽  
Organic Nitrogen ◽  
Edge Structure ◽  
X Ray ◽  
Soil Organic Nitrogen ◽  
Nitrogen Determination ◽  
X Ray Absorption

Mulching Effects on Labile Soil Organic Nitrogen Pools under a Spring Maize Cropping System in Semiarid Farmland

2015 ◽  
Vol 107 (4) ◽  
pp. 1465-1472 ◽  
Author(s):  
Shasha Luo ◽  
Lin Zhu ◽  
Jianliang Liu ◽  
Lingduo Bu ◽  
Shanchao Yue ◽  
...  
Keyword(s):  
Organic Nitrogen ◽  
Cropping System ◽  
Soil Organic Nitrogen ◽  
Nitrogen Pools ◽  
Spring Maize

Radioimmunological determination of somatomedin B in healthy children and in children with growth disturbances

1983 ◽  
Vol 102 (1) ◽  
pp. 16-20 ◽  
Author(s):  
S. Wirth ◽  
W. Schönberger ◽  
A. Roth ◽  
W. Grimm
Keyword(s):  
Pubertal Development ◽  
Growth Delay ◽  
First Year ◽  
Healthy Children ◽  
Older Children ◽  
Primordial Dwarfism ◽  
Constitutional Growth Delay ◽  
The Mean ◽  
Radioimmunological Determination

Abstract. Serum somatomedin B levels were determined by radioimmunoassay in 209 healthy boys and girls from one month to 16 years of age. Low values were found up to the second year life. In the first year the mean level was 13.8 mg/l in girls and 11.5 mg/l in boys. In older children the values increased to levels between 13 and 22 mg/l in boys and between 13 and 18.5 mg/l in girls. They were independent of the stage of pubertal development. Somatomedin B levels were normal in 71 children with constitutional growth delay, primordial dwarfism, familial dwarfism and other forms of growth disturbance. The mean levels were between 12.1 and 14.4 mg/l. Values below 6 mg/l were present only in children with hGH deficiency. In these patients we could find an increase of the mean level from 4.3 mg/l without therapy to 9.4 mg/l under treatment. Thus the determination of somatomedin B seems to be useful for the diagnosis of hGH deficiency.

Comparative study of five hydrolytic methods in the determination of soil organic nitrogen compounds

1997 ◽  
Vol 28 (15-16) ◽  
pp. 1303-1309 ◽  
Author(s):  
F. A. de O. Camargo ◽  
C. Gianello ◽  
C. Vidor
Keyword(s):  
Comparative Study ◽  
Organic Nitrogen ◽  
Nitrogen Compounds ◽  
Soil Organic Nitrogen

Improvements in the method for fractional determination of soil organic nitrogen

1980 ◽  
Vol 26 (4) ◽  
pp. 469-481 ◽  
Author(s):  
Koyo Yonebayashi ◽  
Tomoo Hattori
Keyword(s):  
Organic Nitrogen ◽  
Soil Organic Nitrogen

scholarly journals Repeatability and Reproducibility of Determination of the Nitrogen Content of Fishmeal by the Combustion (Dumas) Method and Comparison with the Kjeldahl Method: Interlaboratory Study

2007 ◽  
Vol 90 (1) ◽  
pp. 6-20 ◽  
Author(s):  
Eric L Miller ◽  
Anthony P Bimbo ◽  
Stuart M Barlow ◽  
Berni SHeridan ◽  
L B W Burks ◽  
...  
Keyword(s):  
Nicotinic Acid ◽  
Nitrogen Content ◽  
Organic Nitrogen ◽  
Mean Value ◽  
Reliable Measure ◽  
Relative Standard ◽  
Kjeldahl Method ◽  
Repeatability And Reproducibility ◽  
The Mean

Abstract Ten fishmeal samples (hidden duplicates of 4 meals plus 2 high-protein meals as a Youden pair), tryptophan, and nicotinic acid were analyzed by 18 laboratories using the Dumas method. Thirteen of the laboratories also analyzed the same 12 samples using their current Kjeldahl method. Recoveries (± sR) of tryptophan and nicotinic acid were 99.3 ± 1.04 and 98.8 ± 2.11 by Dumas and 97.1 ± 3.03 and 74.6 ± 26.76 by Kjeldahl. The Dumas method gave significantly greater values (P < 0.001) than the Kjeldahl method. For fishmeals, Kjeldahl N 0.989 of Dumas N (P < 0.001). A similar proportionate difference (0.984 of Dumas N) was observed with tryptophan. Most laboratories failed to determine nicotinic acid correctly by Kjeldahl. For fishmeals, the relative standard deviations for repeatability and reproducibility were for Dumas 1.48 and 2.01% and Kjeldahl 1.62 and 2.37%, respectively. A single analysis conducted in 2 laboratories should not differ by more than 5.63% of the mean value when measured by Dumas or by more than 6.64% by Kjeldahl. It is concluded that with fishmeal, Dumas gives a more reliable measure of organic nitrogen than Kjeldahl, and, therefore, Dumas should be the method of choice.

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