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[en] The purpose of this work was to augment the alkaline protease production from Bacillus subtilis by using chemical mutagen (MMS) and UV mutagenesis. A number of mutants were isolated which produce high levels of extra cellular proteases. Analysis of culture supernatants of these mutants had shown that the total amounts of proteolysis activity were increased from 1 to 2 fold over the wild strain. Clones showing promote response were further characterized by analyzing different parameters; like of Temperature, pH substrate concentration and incubation period, to study the activity of protease enzyme. (author)
[en] The influence of various culture conditions on protease production by Bacillus subtilis ML-4 was studied in the presence of growth medium containing poultry feed waste (5%), K/sub 2/HPO/sub 4/ (0.3%), CaCl/sub 2/ (0.03%) and MgSO/sub 4/ (0.015%). Maximum protease production (264.25 +- 1.86 U/ml) was observed at initial pH 9 with 3% (v/v) of inoculum size after 48 h of incubation at 37 degree C. The alkaline protease was stable over a broad range of temperature (30 to 60 degree C) and pH (8 to 11). However, maximum activity (155.45 U/ml) was observed at temperature 50 degree C and pH 10. (author)
[en] The reclamation of salt affected soils needs the addition of soil amendment and enough water to leach down the soluble salts. The operations may also include other simple agronomic techniques to reclaim soils and to know the crops and varieties that may be grown and other management practices which may be followed on such soils (Khan, 2001). The choice of crops to be grown during reclamation of salt affected soils is very important to obtain acceptable yields. This also decides cropping systems as well as favorable diversification for early reclamation, desirable yield and to meet the other requirements of farm families. In any salt affected soils, the following three measures are adopted for reclamation and sustaining the higher productivity of reclaimed soils. 1. Suitable choice of crops, forestry and tree species; 2. Suitable choice of cropping and agroforestry system; 3. Other measures to sustain the productivity of reclaimed soils. (author)
[en] Among the regulatory requirements to satisfy in one first stage, before the beginning of the construction of a nuclear facility, it should be carried out a radiological analytic theoretical study that, with base in the technological characteristics of the power station proposal and making use of the environmental parameters, determine the ecological routes that can carry out to groups of population considered as critical those radionuclides with possibility to be liberated. Also, this study understands the estimate of the equivalent doses for external and internal exhibition that those critical groups would receive real or potentially as a consequence of the normal activity of the power station
[en] Precision agriculture is a management approach for sustainable agriculture. It can be applied even in small fields. It aims to optimize inputs, improve profits, and reduce adverse environmental impacts. In this study, a series of measurements were conducted over three growing seasons to assess variability in a 0.55 ha pear orchard located in central Greece. Soil ECa was measured using EM38 sensor, while soil samples were taken from a grid 17 × 8 m and analysed for texture, pH, P, K, Mg, CaCO3, and organic matter content. Data analysis indicated that most of the nutrients were at sufficient levels. Soil and yield maps showed considerable variability while fruit quality presented small variations across the orchard. Yield fluctuations were observed, possibly due to climatic conditions. Prescription maps were developed for nitrogen variable rate application (VRA) for two years based on the replacement of the nutrients removed by the crop. VRA application resulted in 56% and 50% reduction of N fertiliser compared to uniform application.
[en] This issue of the Newsletter reports on status of technical cooperation projects, research coordination meetings and training courses offered on Soil, Water and Nutrient Management and staff related news at the Soil and Water Management and Crop Nutrition Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture
[en] A radiological or nuclear incident could be characterized by high activity doses and high number of persons exposed. It is necessary to give a prompt response in order to know the number of exposed to internal contamination, to evaluate the contamination levels in each person and even to identify the radionuclides involved.In vitro laboratories routine monitoring measurements employed to quantify alpha and betta emitters in urine require radiochemical separation and long counting time, which implies a minimum of 1 or 2 weeks to obtain the results. In this work, rapid radiochemical separation method applied directly to urine is presented. Pu isotopes, Am and Cm isotopes, Uranium isotopes, Thorium isotopes, 90Sr, Tritium, 14C and 35S are isolated, measured by alpha spectrometry and liquid scintillation counting and quantify their activities. Finally, results of the participation in European Radiation Dosimetry Group intercomparison on Emergency Bioassay, Bundesamt für Strahlenschutz exercise and the Global Health Security Initiative / Radio-Nuclear Threats Working Group emergency intercomparison exercise validate the accuracy of this procedure
[es]Una emergencia radiológica o nuclear se puede caracterizar por dosis altas de actividad y un elevado número de personas afectadas. Una respuesta rápida y eficiente es imprescindible para conocer el alcance en la población afectada e incluso, para identificar los radionucleidos involucrados en la posible contaminación interna. Los laboratorios de medidas in vitro de los servicios de Dosimetría Interna emplean programas de monitorización en rutina para la cuantificación de actividad de emisores alfa y beta en muestras biológicas (bioensayos) aplicando protocolos de separación radioquímica y técnicas de medida con largos tiempos de contaje. Su aplicación permite alcanzar muy bajos niveles de detección, pero el largo periodo de procesamiento de la muestra hasta la obtención de resultados hace que este tipo de protocolos sean, a priori, incompatibles con la situación de emergencia previamente planteada. Se presenta en este trabajo, un procedimiento radioquímico rápido y secuencial aplicado a muestras de orina, que permite en un solo día separar en la misma muestra los siguientes radionucleidos: isótopos de Pu, Am, Cm, U, Th, 90Sr, 3H, 14C y 35S. Sobre las fracciones de muestra aisladas se aplican las técnicas de medida de espectrometría alfa y espectrometría de centello en fase líquida y espectrometría de masas, obteniéndose resultados de actividad en un tiempo inferior a los dos días. Este procedimiento ha sido validado mediante la participación en los ejercicios de intercomparación internacional para bioensayos en situaciones de emergencia organizados por Eurados (European Radiation Dosimetry Group), BfS (Bundesamt für Strahlenschutz –organismo regulador alemán–) y por la Iniciativa Global de Seguridad Sanitaria (GHSI) en colaboración con WHO y el OIEA comprobándose el grado de exactitud y precisión de los excelentes resultados obtenidos así como la capacidad de análisis, los tiempos de contaje, la actividad mínima detectable, el número de muestras a tratar simultáneamente o el tiempo de respuesta global.
[en] Two field experiments had been conducted at Sembawa Field Exp. Sta. to screen some Bradrhyzohium inoculants on soybean mutant lines with liming rate of 0.6 t/ha similar to the technique used by farmers in soybean pilot plant at Mesuji, South Sumatera (banded at planting row on soil surface) three days prior to planting row on soil surface) three day as prior to planting. The first experiment screened single strains B-22, TAL 102, and mixed inoculants (B-22+TAL 102) on soybean mutant lines No.55, 58, 76-A, and cv. Wilis. The second experiment screened some mixed inoculants (B-22+B-28), (B-22+B37), (B-22+FA 3), (B-22+G49), and (B-22+TAL 102) on two soybean mutant lines No. 55 and 58. The soybean were grown in between two year old rubber plants. Nodulation, plant growth were observed at early pod filling (R5), and N yield at this stage were determined. Amount of N derived from fixation was determined by N difference method. Result from two experiments showed that soybean mutant line No 58 was more responsive to inoculation compared to the other mutant lines No.55, 76-A, and cv. Willis. Banded liming at plant rows on soil surface could not induce good nodulation in the land with high Al saturation (68%). Growth and N yield control plant was very low ranging from 11-16 g/10 plants and 678-943 mg N10 plants. Inoculation enhanced plant growth nearly twice, and plant N yield range from 678 to 943 mg N/10 plants. This amount was only 60% of the N yield when line was given at 2 t/ha broadcasted. To enhance good plant growth when using this cultural technique, it was suggested to add organic matter or soil amendment found abundant in the area, such as manure, sawdust or rice husk ash. (author)