Continuous cropping of endangered therapeutic plants via electron beam soil treatment and neutron tomography

Various medicinal plants are threatened with extinction owing to their over exploitation and the prevalence of soil borne pathogens. In this study, soils infected with root rot pathogens, which prevent continuous cropping, were treated with an electron beam. The level of soil borne fungus was reduced to amp; 8804;0.01 by soil electron beam treatment without appreciable effects on the levels of antagonistic microorganism or on the physicochemical properties of the soil. The survival rate of 4 year old plant was higher in electron beam treated soil 81.0 than in fumigated 62.5 , virgin 78 , or untreatedreplanting soil 0 . Additionally, under various soils conditions, neutron tomography permitted the monitoring of plant health and the detection of root pathological changes over a period of 4 6 years by quantitatively measuring root water content in situ. These methods allow continual cropping on the same soil without pesticide treatment. This is a major step toward the environmentally friendly production of endangered therapeutic herb

Samples to Determine the Resolution of Neutron Radiography and Tomography

Knowing the resolution and effective pixel size of an imaging system is essential for dimensional and quantitative measurements. A collection of test devices was developed for neutron imaging that can be used to quantify pixel and voxel size, resolution of the imaging system, and beam divergence. The first set of devices is intended for measurements with radiographs using test patterns or an absorbing edge. For tomography, Al vials were filled with Ti spheres of increasing dimensions in each vial. Ti was chosen since it provides sufficient contrast while the transmission is still guaranteed. The first resolution criterion was to determine from which vial that the spheres can be uniquely identified as spheres. More complex analysis would involve measuring the volume of the spheres or even to compute the edge spread function analogous to the method with the knife edge for radiographs. For the edge analysis, a larger Ti sphere was considered. Using a sphere for the edge spread function analysis allowed for determination of the resolution in any direction. Images acquired using the different test items are included and methods to perform the analysis required to quantify the resolution from the images are propose