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The use of a cusp magnetic field is studied to improve the thrust performance of small electrodeless radio frequency (RF) plasma thrusters based on a theoretical analysis of a magnetized inductively coupled plasma. In this type of thruster, electrons play a critical role in determining the thrust performance. The electron energy probability function (EEPF) and two-dimensional profiles of the plasma parameters in the cusp-type magnetic field RF thruster are investigated to characterize the plasma flow. Non-Maxwellian EEPFs were obtained, which correspond to the pressure and plasma potential profiles in the plasma plume. In addition, the axial ion velocity was measured, and the presence of ion flux in the downstream direction is revealed, indicating ideal ion acceleration. [ABSTRACT FROM AUTHOR]

Focuses on the effectivity of Helicobacter pylori stool antigen in real-time monitoring of Helicobacter pylori eradication therapy. Usefulness of a non-invasieve antigen-based assay; Information on the eradication therapy undertaken on children; Results of the therapy.

Primary lymphoma of the central nervous system (PCNSL) is extremely rare, especially in childhood. A 9-year-old Japanese boy was diagnosed as having precursor-B cell-type lymphoblastic lymphoma, based on morphologic and immunocytochemical analysis of mononuclear cells in the cerebrospinal fluid and a positive reaction for terminal deoxynucleotidyl transferase (TdT), CD19, CD79a, and CD179b. After seven courses of chemotherapy and craniospinal radiotherapy, the patient is alive, well, and in continuous complete remission. Despite its rarity, PCNSL should be included in the differential diagnosis in the presence of symptoms of increased intracranial pressure and/or unusual imaging findings of the brain.

From the culture supernatant of Staphylococcus aureus Wood 46, we obtained a naturally-occurring nicked molecule of staphylococcal alpha-toxin. The nicked alpha-toxin consisted of non-covalently-linked 8-kDa and 25-kDa polypeptides, which were derived, respectively, from the N-terminal and the C-terminal part of the toxin nicked at the peptide bond between Glu-71 and Gly-72. The nicked toxin, as well as native alpha-toxin, bound to and oligomerized in the liposome membranes composed of choline-containing phospholipids (i.e., phosphatidylcholine and sphingomyelin) and cholesterol, and formed membrane channel in the liposome membranes. However, the channel-forming activity of the nicked toxin, assessed as a toxin-induced carboxyfluorescein leakage from the liposomes, was approx. 20-fold lower than that of native alpha-toxin. Channel-forming activity of the nicked toxin as well as native toxin was inhibited by divalent cations including Zn2+, Cd2+, Ca2+ and Mg2+, and degree of the inhibitory effect of the divalent cations was in the following order: Zn2+ > Cd2+ > Ca2+ > Mg2+. Thus, although the cleavage of alpha-toxin at the position between Glu-71 and Gly-72 drastically reduced channel-forming activity of the toxin, the nicked toxin retained the ability to oligomerize in phospholipid-cholesterol membranes and the characteristics of channel-forming activity in terms of the specificity for phospholipids and the susceptibility to divalent cations.