Resistive switching (RS) was demonstrated in four-terminal planar memristive devices fabricated on reduced TiO (TiO) single crystal substrates. In the device, a pair of diagonally opposing electrode terminals is used to modify the distribution of oxygen vacancies in the region between another pair of diagonally opposing electrode terminals. This allowed microscopic visual observations of the oxygen vacancy distribution based on electrocoloring.
View Article and Find Full Text PDFA high-Ge-content SiGe/compositionally graded SiGe-stacked structure grown on Si(001) is now considered to be an important platform for the realization of advanced nanometer-scale complementary metal oxide semiconductor devices with high-mobility channel materials, such as III-V materials and Ge, and monolithically integrated photonic modules. The performance of such advanced devices is critically influenced by crystalline inhomogeneity in the stacked structure; therefore, precise characterization of the crystallinity is important. In particular, the development of a characterization method not only for in-plane crystallinity but also for in-depth crystallinity is strongly required.
View Article and Find Full Text PDFThe high electrical and drastically-low thermal conductivities, a vital goal for high performance thermoelectric (TE) materials, are achieved in Si-based nanoarchitecture composed of Si channel layers and epitaxial Ge nanodots (NDs) with ultrahigh areal density (~10(12) cm(-2)). In this nanoarchitecture, the ultrasmall NDs and Si channel layers play roles of phonon scattering sources and electrical conduction channels, respectively. Electron conductivity in n-type nanoacrhitecture shows high values comparable to those of epitaxial Si films despite the existence of epitaxial NDs.
View Article and Find Full Text PDFPhonon transport in Si films was controlled using epitaxially-grown ultrasmall Ge nanodots (NDs) with ultrahigh density for the purpose of developing Si-based thermoelectric materials. The Si/Ge ND stacked structures, which were formed by the ultrathin SiO2 film technique, exhibited lower thermal conductivities than those of the conventional nanostructured SiGe bulk alloys, despite the stacked structures having a smaller Ge fraction. This came from the large thermal resistance caused by phonon scattering at the Si/Ge ND interfaces.
View Article and Find Full Text PDFIn 13 of 43 non-beta-hemolysin-producing bovine isolates of Staphylococcus aureus, two truncated beta-hemolysin (hlb) genes were demonstrated by PCR and sequencing, and one truncated hlb gene was located beside the integrase (int) gene of phage origin. The staphylokinase (sak) gene was detected in all 13 isolates in which the truncated hlb genes were detected by PCR. Enterotoxin A (sea) and enterotoxin P (sep) genes were also detected in 5 and 2 of the 13 isolates, respectively.
View Article and Find Full Text PDFLeukotoxin family genes in Staphylococcus aureus isolated from domestic animals were examined by polymerase chain reaction. LukS and lukF genes were detected in all 48 avian and 72 porcine isolates of S. aureus.
View Article and Find Full Text PDFAn exfoliative toxin produced by Staphylococcus aureus is the causative agent of staphylococcal scalded-skin syndrome (SSSS) in young children. Recently, we reported that only few isolates of S. aureus from bovine mastitis contained the eta gene encoding exfoliative toxin A (ETA) and produced ETA in vitro.
View Article and Find Full Text PDFPyolysin (PLO), secreted by Arcanobacterium pyogenes, is a novel member of the thiol-activated cytolysin (TACY, cholesterol-dependent cytolysin) family of bacterial toxins. Recently, we demonstrated that the epitopes of monoclonal antibodies (mAbs) S, H, C, and G lie in the regions of amino acids regions 55-73, 123-166, 482-506, and 482-506 of PLO, respectively, by the reaction of mAbs with truncated PLOs. In this study, we substituted the amino acids in these epitope regions of PLO by site-directed mutagenesis and examined the effect of these amino acid substitutions.
View Article and Find Full Text PDFRecently whole genome sequencing of Staphylococcus aureus has revealed the genes encoding cysteine proteases such as staphopain and SspB. In this study, we cloned and sequenced the structural gene (ScpA) encoding a cysteine (thiol) protease of S. aureus strain CH-91 from a chicken with dermatitis using polymerase chain reaction (PCR) and inverse PCR methods.
View Article and Find Full Text PDFThe gene (aur) encoding the metalloprotease (aureolysin) of Staphylococcus aureus from domestic animals was analyzed by polymerase chain reaction (PCR), PCR-restriction fragment length polymorphism (PCR-RFLP) and sequencing. The aur gene was detected in all 74 isolates from cows, pigs and chickens by PCR amplification and was classified into types I and II by PCR-RFLP patterns. The type II aur gene was contained in 36 (94.
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