Characterization of Virulence Plasmids and Serotyping of Rhodococcus equi Isolates from Submaxillary Lymph Nodes of Pigs in Hungary

The plasmid types and serotypes of 164 Rhodococcus equi strains obtained from submaxillary lymph nodes of swine from different piggeries in 28 villages and towns located throughout the country were examined. The strains were tested by PCR for the presence of 15- to 17-kDa virulence-associated protein antigen (VapA) and 20-kDa virulence-associated protein antigen (VapB) genes. Plasmid DNAs were isolated and analyzed by digestion with restriction endonucleases to estimate size and compare their polymorphism characteristics. None of the 164 isolates contained the vapA gene, and 44 (26.8%) isolates were positive for the vapB gene, showing a product of the expected 827-bp size in the PCR amplification. The 44 isolates of intermediate virulence contained virulence plasmids that were identified as types 1 (3 isolates), 4 (1 isolate), 5 (36 isolates), 6 (1 isolate), and 7 (2 isolates) and as a new variant (1 isolate). On the basis of restriction digestion patterns of plasmid DNAs, we tentatively designated the variant as type 17. Use of the serotyping method of Prescott showed that 110 (67.1%) out of the 164 isolates were typeable and that serotype 2 predominated (83 isolates [50.6%]), followed by serotype 1 (26 strains [15.9%]). Only one isolate belonged to serotype 3. A total of 54 (32.9%) isolates were untypeable in Prescott's system. The prevalence of R. equi strains of intermediate virulence among the isolates that came from the submaxillary lymph nodes of swine in Hungary was lower than that seen with isolates obtained elsewhere

Concept design of a superconducting magnet for a compact heavy-ion synchrotron

A compact synchrotron is now under development at the Nation-al Institutes for Quantum Science and Technology (QST), with the goal of downsizing the heavy-ion therapy system with super-conducting magnets conduction-cooled by GM cryocoolers. The synchrotron is required to accelerate several kinds of heavy-ion beams from 4 MeV/u to 430 MeV/u. A superconducting magnet with both dipole and quadrupole coils is adopted to generate a dipole field from 0.3 to 3.5 T and a quadrupole field from 0.1 to 1.5 T/m with a ramp rate of 0.6 T/s. A coil winding pattern and iron yoke are optimized to achieve field homogeneity in the re-quired area. For the small-scale synchrotron, the coil ends are op-timized with a novel parameter combining the beta function and multipole errors considering the beam dynamics

Electromagnetic design of the superconducting magnet for a compact heavy-ion synchrotron

A project to develop a compact heavy ion therapy device has been initiated at the National Institutes for Quantum and Radiological Science and Technology . The therapy device uses a 430 MeV/u synchrotron with superconducting bending magnets as a main accelerator. In order to reach the required output of the heavy ion beam, the bending magnets have been designed to be operate dalternately from 0.3 T (for to 3.5 T maximum (for extraction) at the ramping rate of 0.6 T/s. The 3D electromagnetic design of the synchrotron bending magnet has been performed. The magnetic length is 1.49 m for 45 degree bending angle, and curvature radius is 1.89 m. The superconducting coil consists of a low loss NbTi wire with a 1 mm diameter , and t he maximum operating current is 265A. To suppress the magnetomotive force, t he cross sectional coil designadopt ed an elliptical shaped arrangement. The coil and iron yoke designs were optimized for the uniformity of the magnetic field in the required area In addition, a short straight model with a magnetic length of 400 mm w as fabricated for the feasibility demonstration. The results of the excitation test as well as the electromagnetic design will be reported.27th International Conference on Magnet Technolog