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The annealing behaviors of oxygen vacancies introduced by the epitaxial growth of thin SrTiO3 and Al2O3 films on SrTiO3 substrates were studied by using a monoenergetic positron beam. The films were grown by molecular-beam epitaxy without using an oxidant. The Doppler broadening spectra of the annihilation radiation were measured as a function of the incident positron energy for samples fabricated under various growth conditions. The line-shape parameter S, corresponding to the annihilation of positrons in the substrate, was increased by the film growth, suggesting diffusion of oxygen from the substrate into the film and a resultant introduction of vacancies (mainly oxygen vacancies). A clear correlation between the value of S and the substrate conductivity was obtained. From isochronal annealing experiments, the Al2O3 thin film was found to suppress the penetration of oxygen from the atmosphere for annealing temperatures below 600 °C. Degradation of the film’s oxygen blocking property occurred due to the annealing at 700 °C, and this was attributed to the oxidation of the Al2O3 by the atmosphere and the resultant introduction of vacancy-type defects. [ABSTRACT FROM AUTHOR]

Understanding tumor-induced angiogenesis is a challenging problem with important consequences for the diagnosis and treatment of cancer. In this study, we define a novel function for epithelial membrane protein-2 (EMP2) in the control of angiogenesis. EMP2 functions as an oncogene in endometrial cancer, and its expression has been linked to decreased survival. Using endometrial cancer xenografts, modulation of EMP2 expression resulted in profound changes to the tumor microvasculature. Under hypoxic conditions, upregulation of EMP2 promoted vascular endothelial growth factors (VEGF) expression through a HIF-1α-dependent pathway and resulted in successful capillary-like tube formation. In contrast, reduction of EMP2 correlated with reduced HIF-1α and VEGF expression with the net consequence of poorly vascularized tumors in vivo. We have previously shown that targeting of EMP2 using diabodies in endometrial cancer resulted in a reduction of tumor load, and since then we have constructed a fully human EMP2 IgG1. Treatment of endometrial cancer cells with EMP2-IgG1 reduced tumor load with a significant improvement in survival. These results support the role of EMP2 in the control of the tumor microenvironment and confirm the cytotoxic effects observed by EMP2 treatment in vivo. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to analyse microbiota of the fermented food ' narezushi', an archetype of modern Japanese sushi. The pyrosequencing technique was used to analyse sequences of 16S ribosomal DNA contained in six narezushi products. Methods and Results: The V1-V2 regions of the 16S ribosomal DNA were amplified from different narezushi products using PCR, and approximately 120 000 sequences were phylogenetically assigned at the genus level, using the Ribosomal Database Project classifier. In all samples, the microbial populations consisted of more than 90% Lactobacillales, mainly Lactobacillus or Pediococcus, reflecting their crucial role in narezushi fermentation. There were more than 700 operational taxonomy units in all samples, with Shannon-Wiener index varying from 1·69 to 2·60. Conclusions: The microbiota of all narezushi products were shown to consist largely of Lactobacillales populations. Interestingly, different species were found to be dominant in each product. Significance and Impact of the Study: This study provides an insight into the bacterial composition of fermented fish-based foods, which are consumed worldwide. Significant differences in the dominant species were observed between products, possibly because of the starter-free production process. [ABSTRACT FROM AUTHOR]

The growths of BaTiO3 films on interfacial SiO2 were carried out with molecular beam epitaxy (MBE) in various oxygen partial pressures. In the BaTiO3 growth on 2 nm-thick SiO2 film at the oxygen partial pressure of less than 4.8×10−5 Pa, concavities at the BaTiO3 film surface and the Si/SiO2 interface appeared and the Si atoms diffused from the Si substrate to the top BaTiO3 layer. These were observed only after the film growth in the low oxygen pressure and only on ultrathin interfacial SiO2. And the silicide material was formed within the concavity. These results indicate that 2 nm-thick SiO2 film is not enough to the suppression of the reaction of the metal atoms with Si substrate. [Copyright &y& Elsevier]

Vacancy-type defects in SrTiO3 were studied by means of positron annihilation. Thin CeO2 films were grown on SrTiO3 substrates by molecular-beam epitaxy without using an oxidant; oxygen was supplied by diffusion from the substrate. This process is referred as “auto-feeding epitaxy” (AFE). The species of defects introduced into the substrate was found to be not only oxygen vacancies but also Sr-vacancies or their complexes. CeO2 films were grown also on MgO, yttria-stabilized zirconia and sapphire substrates using AFE, and these substrates were characterized by positron annihilation. [Copyright &y& Elsevier]

Vacancy-type defects in the CeO[sub 2]/SrTiO[sub 3] structure were studied by means of positron annihilation. Thin CeO[sub 2] films were grown on SrTiO[sub 3] substrates by molecular-beam epitaxy without using an oxidant; oxygen was supplied by diffusion from the substrate (this process is referred to as automatic feeding epitaxy). A preferential epitaxial growth of CeO[sub 2](001) on SrTiO[sub 3](001) was observed, but an increase in the film thickness or annealing in an O[sub 2] atmosphere caused a partial growth of CeO[sub 2](110). The introduction of this phase was found to correlate with the reduction in the concentration of vacancy-type defects. The species of defects introduced into the SrTiO[sub 3] substrate was found to be not only oxygen vacancies but also Sr vacancies or their complexes. We discuss the mechanism that introduced cation vacancies in terms of oxygen nonstoichiometry. We found the trapping rate of positrons by Sr vacancies to depend on the sample temperature. This was associated with the temperature dependence of the dielectric constant near the defects or the presence of shallow trapping centers. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Introduction Some patients with acute phase schizophrenia are too agitated to receive treatment in a normal hospital room. They must be isolated for the treatment. Although the stay in an isolation room seems harmful to patients, no study detailing the stress response to isolation with objective measures has been conducted. Method Nine patients with schizophrenia or schizoaffective disorder were recruited (mean age = 52 years, male = 3, schizophrenic = 7). At the time of evaluation, they were staying in an isolation room. To evaluate stress response to the environment, the level of salivary amylase was tested when the patients were either in the isolation room (T1) or out of the isolation room (T2). T2 was defined as one hour after the room's door was opened. The data were analyzed by the Wilcoxon rank-sum test. Result There is a significant difference between the median (range) levels of salivary amylase at T1 and T2 (19 [2–146] vs 44 [9–178], respectively, P = 0.021). Discussion The data demonstrate that the stress response at T2 was stronger than that at T1, which suggests that the isolation room environment is less stressful to the patient compared to being outside the room. An environment that has many potential stimuli, such as the presence of other patients and a television in the lobby, may be harmful to patients with acute phase schizophrenia. Therefore, although the isolation room is apparently harmful, it could, in fact, have a positive effect on patients. [ABSTRACT FROM AUTHOR]

Summary: Metallic materials are known to be very sensitive to Gallium (Ga) focused ion beam (FIB) processing. Crystal defects formed by FIB irradiation degrade the transmission electron microscope image quality, and it is difficult to distinguish original defects from FIB process‐induced damage. A solution to this problem is the low acceleration voltage and low incident angle (LVLA) Argon ion milling, which can be incorporated as an extensional countermeasure for FIB damage removal and eventually for preparation of high‐quality lamellae. The transmission electron microscope image quality of iron single crystal could be improved by removing crystal defects using the low acceleration voltage and low incident angle Argon ion milling finish. Lamella quality of the processing result was almost similar with that of the conventional electrolytic polishing. As a practical application of the process, low damage lamella of stainless cast steel could be prepared. Effectiveness of the FIB system equipped with the low acceleration voltage and low incident angle Argon ion milling function as a tool to make high‐quality metallic material lamellae is illustrated. [ABSTRACT FROM AUTHOR]