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Mucosal-associated invariant T (MAIT) cells, a blossoming member of the innatelike T cells, play a pivotal role in host defense through engaging the mucosal immunity. Although it has been suggested that MAIT cells are somehow implicated in the allergic airway inflammation mediated by group 2 innate lymphoid cells (ILC2s) such as asthma, the precise role(s) of MAIT cells in such inflammation has remained elusive. To explore the possible roles of MAIT cells in the inflammation, we examined whether MAIT cells suppressed the production of T helper (Th) 2 and inflammatory cytokines from ILC2s, and constrained the proliferation of ILC2s, both of which are prerequisite for airway inflammation. Given that laboratorymice are poor at MAIT cells, a novel mouse line rich inMAIT cells was used. We found that mice rich in MAIT cells showed alleviated airway inflammation as evidenced by reduced infiltration of the immune cells and hyperplasia in goblet cells in the lung concomitant with compromised production of Th2 and inflammatory cytokines, while wild type mice exhibited severe inflammation upon challenge with the fungal extracts. In vitro coculture experiments using purified ILC2s and MAIT cells unrevealed that cytokinestimulated MAIT cells suppressed ILC2s to produce the cytokines as well as to proliferatemost likely via production of IFN-γ. Furthermore, reconstitution of the allergic airway inflammation in the highly immunocompromised mice showed that ILC2-mediated inflammation was alleviated in mice that received MAIT cells along with ILC2s. We concluded that MAIT cells played a crucial role in suppressing the cytokine-producing capacity of ILC2s and ILC2 proliferation, that ultimately led to decrease in the allergic airway inflammation. The results open up a novel therapeutic horizon in ILC2-mediated inflammatory diseases by modulating MAIT cell activity. [ABSTRACT FROM AUTHOR]

Graphite-reinforced 5083 aluminum matrix composites were successfully fabricated via friction stir processing. The graphite-reinforced aluminum alloy sheet sintered at 550°C in a vacuum atmosphere was applied as a reinforcement. Grain refinement and many minute aluminum carbides (Al4C3) were observed in the composites fabricated. The tensile strength of the composites fabricated with the 550°C sintered sheets considerably increased by 64 percent, and the sliding wear characteristics of the composites were appreciably improved compared with that of the base material. [ABSTRACT FROM AUTHOR]

[Introduction] The number of prior studies has reported that mental health problems related to Japanese school teachers have increased sharply during the last two decades, and have become a severe problem for school administration, as well as Japanese society. Therefore, this study is to develop a high school teacher-specific version of four stress-related scales, and to examine the hypothesis, based on the school stress model that stressors, self-efficacy, and coping predict teachers stress reactions. [Methods] The sample of this study included 368 Japanese high school teachers (248 male and 120 female, mean age =42.2, SD=8.2). The participants voluntarily responded to a questionnaire survey that was composed of items in the teacher-specific stressor scale, the self-Efficacy scale, the coping scale, and the stress reaction scale. Exploratory factor analyses, confirmatory factor analyses, and reliability analyses were conducted to develop the four original scales・ The hierarchical regression analyses were performed to confirm the relationships between the four scales.【Results】 The results of exploratory factor analyses indicated that the Stressor Scale, the Self-Efficacy Scale, the Coping Scale, and the Stress Reaction Scale consisted of two factors. All the subscales had satisfactory internal consistency as indicated by Cronbach's alpha reliabilities, and fit indices of structural validities. The results of hierarchical regression analyses indicated that gender, stressors, self-efficacy, and coping, predicted stress reactions. Contrary to the hypothesis of this study, both approach and avoidance coping were associated with higher stress levels. Moreover, there was a limited impact of self-efficacy on the relationship between the stressor and the stress reaction, whereas coping failed to moderate the impact of stressors on stress reactions. 【Conclusion】 These results suggest that mental health interventions for reducing teachers' stress burden should focus on addressing the causes of stress, as well as enhancing the teachers' self-efficacy. Furthermore, more targeted support is needed for female teachers given their reports of elevated stress levels. [ABSTRACT FROM AUTHOR]

Background: Intelectin-1 (ITLN-1) is secreted by intestinal goblet cells and detectable in blood. Its expression is increased in IL-13-overexpressing mouse airways. However, its expression and function in human airways is poorly understood. Methods: Distal and proximal bronchial epithelial cells (BECs) were isolated from bronchoscopic brushings of disease control (D-CON), COPD, inhaled corticosteroid-treated asthma (ST-Asthma) and inhaled corticosteroid-naïve asthma (SN-Asthma) patients. ITLN-1 mRNA expression in freshly isolated BECs, primary cultured BECs with or without IL-13 and inhibition effects of mometasone furoate (MF) were investigated by quantitative real-time PCR (qPCR). Correlations between ITLN-1 mRNA and Type-2 related parameters (e.g. FeNO, IgE, iNOS, CCL26, periostin and DPP4 mRNA) were analyzed. ITLN-1 protein distribution in asthmatic airway tissue was assessed by immunohistochemistry. Bronchial alveolar lavage (BAL) and serum ITLN-1 protein were measured by ELISA. The effect of recombinant human (rh) ITLN-1 on stimulated production of CXCL10 and phospho(p)-STAT1 expression examined in lung fibroblasts. Results: ITLN-1 mRNA was expressed in freshly isolated BECs and was correlated with Type-2 related parameters. ITLN-1 protein was increased in goblet cells in SN-Asthmatics and increased in SN-Asthmatic BAL fluid. There were no any differences in serum ITLN-1 concentration between ST and SN-Asthma. IL-13 enhanced ITLN-1 expression and inhibited by MF from BECs in vitro, while rhITLN-1 inhibited CXCL10 production and p-STAT1 expression in HFL-1 cells. Conclusion: ITLN-1 is induced by IL-13 and expressed mainly in goblet cells in untreated asthma where its levels correlate with known Type-2 related parameters. Further, ITLN-1 inhibits Type-1 chemokine expression. [ABSTRACT FROM AUTHOR]

To evaluate dislocations induced by neutron irradiation, we developed a weak-beam scanning transmission electron microscopy (WB-STEM) system by installing a novel beam selector, an annular detector, a high-speed CCD camera and an imaging filter in the camera chamber of a spherical aberration-corrected transmission electron microscope. The capabilities of the WB-STEM with respect to wide-view imaging, real-time diffraction monitoring and multi-contrast imaging are demonstrated using typical reactor pressure vessel steel that had been used in an European nuclear reactor for 30 years as a surveillance test piece with a fluence of 1.09 × 1020 neutronscm-2. The quantitatively measured size distribution (average loop size = 3.6 ± 2.1 nm), number density of the dislocation loops (3.6 × 1022m-3) and dislocation density (7.8 × 1013mm-3) were carefully compared with the values obtained via conventional weak-beam transmission electron microscopy studies. In addition, cluster analysis using atom probe tomography (APT) further demonstrated the potential of the WB-STEM for correlative electron tomography/APT experiments. [ABSTRACT FROM AUTHOR]

Using the atom probe tomography, transmission electron microscopy, and ab initio calculations, we investigate the three-dimensional distributions of oxygen atoms segregating at the typical large-angle grain boundaries (GBs) (Σ3{111}, Σ9{221}, Σ9{114}, Σ9{111}/{115}, and Σ27{552} in Czochralski-grown silicon ingots. Oxygen atoms with a covalent radius that is larger than half of the silicon's radius would segregate at bond-centered positions under tensile stresses above about 2 GPa, so as to attain a more stable bonding network by reducing the local stresses. The number of oxygen atoms segregating in a unit GB area NGB (in atoms/nm2) is hypothesized to be proportional to both the number of the tensilely-stressed positions in a unit boundary area nbc and the average concentration of oxygen atoms around the boundary [Oi] (in at. %) with NGB∼50nbc[Oi]. This indicates that the probability of oxygen atoms at the segregation positions would be, on average, fifty times larger than in bond-centered positions in defect-free regions. [ABSTRACT FROM AUTHOR]

Three-dimensional distribution of impurity atoms was determined at functional ∑5{013} and smallangle grain boundaries (GBs) in as-grown mono-like silicon crystals by atom probe tomography combined with transmission electron microscopy, and it was correlated with the recombination activity of those GBs, CGB, revealed by photoluminescence imaging. Nickel (Ni), copper (Cu), and oxygen atoms preferentially segregated at the GBs on which arrays of dislocations existed, while those atoms scarcely segregated at ∑5{013} GBs free from dislocations. Silicides containing Ni and Cu about 5nm in size and oxides about 1 nm in size were formed along the dislocation arrays on those GBs. The number of segregating impurity atoms per unit GB area for Ni and that for Cu, NNi and NCu, were in a trade-off correlation with that for oxygen, NO, as a function of CGB, while the sum of those numbers was almost constant irrespective of the GB character, CGB, and the dislocation density on GBs. CGB would be explained as a linear combination of those numbers: CGB (in %) ~400(0.38NO+NNi+NCu) (in atoms/nm²). The GB segregation of oxygen atoms would be better for solar cells, rather than that of metal impurities, from a viewpoint of the conversion efficiency of solar cells. [ABSTRACT FROM AUTHOR]

We have demonstrated that it is possible to reproducibly quantify hydrogen concentration in the SiN layer of a SiO2/SiN/SiO2 (ONO) stack structure using ultraviolet laser-assisted atom probe tomography (APT). The concentration of hydrogen atoms detected using APT increased gradually during the analysis, which could be explained by the effect of hydrogen adsorption from residual gas in the vacuum chamber onto the specimen surface. The amount of adsorbed hydrogen in the SiN layer was estimated by analyzing another SiN layer with an extremely low hydrogen concentration (<0.2 at. %). Thus, by subtracting the concentration of adsorbed hydrogen, the actual hydrogen concentration in the SiN layer was quantified as approximately 1.0 at. %. This result was consistent with that obtained by elastic recoil detection analysis (ERDA), which confirmed the accuracy of the APT quantification. The present results indicate that APT enables the imaging of the three-dimensional distribution of hydrogen atoms in actual devices at a sub-nanometer scale. [ABSTRACT FROM AUTHOR]

Background: Type 2 helper T-cell cytokines including IL-13 play a central role in the pathogenesis of bronchial asthma (BA). During the course of our research, our attention was drawn to dipeptidyl peptidase-4 (DPP4) as one of the molecules that were induced from bronchial epithelial cells (BECs) by IL-13 stimulation. DPP4 could become a new biomarker or therapeutic target. The aim of this study was to investigate the expression of DPP4 in the asthmatic airway, and its role in the pathophysiology of asthma.Methods: BECs were isolated from patients with inhaled corticosteroid-treated asthma (stBA) and inhaled corticosteroid-naïve asthma (snBA) using bronchoscopy. DPP4 mRNA expression in freshly isolated BECs and primary cultured BECs with or without IL-13 stimulation was investigated by microarray analysis and quantitative real-time PCR (qPCR). The distribution of DPP4 protein was determined by immunostaining of transbronchial lung biopsy specimens from asthma patients. The effect of recombinant human (rh) DPP4 on the proliferation of lung fibroblasts (HFL-1) and bronchial smooth muscle cells (BSMCs) was examined, as well as its effect on the production of fibronectin (FN).Results: DPP4 mRNA was strongly expressed in freshly isolated BECs in snBA, and its expression was significantly enhanced by IL-13 stimulation. DPP4 mRNA expression in BECs of snBA significantly correlated with exhaled nitric oxide. Biopsied tissues of the asthmatic airway revealed strong expression of DPP4 protein in BECs from snBA subjects. rhDPP4 stimulated the proliferation of HFL-1 and BSMCs, and it also enhanced production of FN from these airway cells.Conclusion: DPP4 may be involved in the pathologic features of asthmatic airway inflammation and cell proliferation and FN production. [ABSTRACT FROM AUTHOR]

Three-dimensional distribution of oxygen atoms at small-angle tilt boundaries (SATBs) in Czochralski-grown p-type silicon ingots was investigated by atom probe tomography combined with transmission electron microscopy. Oxygen gettering along edge dislocations composing SATBs, post crystal growth, was observed. The gettering ability of SATBs would depend both on the dislocation strain and on the dislocation density. Oxygen atoms would agglomerate in the atomic sites under the tensile hydrostatic stress larger than about 2.0GPa induced by the dislocations. It was suggested that the density of the atomic sites, depending on the tilt angle of SATBs, determined the gettering ability of SATBs. [ABSTRACT FROM AUTHOR]

Background: Pulmonary alveolar proteinosis (PAP) is a rare disease occurred by idiopathic (autoimmune) or secondary to particle inhalation. The in-air microparticle induced X-ray emission (in-air micro-PIXE) system performs elemental analysis of materials by irradiation with a proton microbeam, and allows visualization of the spatial distribution and quantitation of various elements with very low background noise. The aim of this study was to assess the secondary PAP due to inhalation of harmful particles by employing in-air micro-PIXE analysis for particles and intracellular iron in parafin-embedded lung tissue specimens obtained from a PAP patient comparing with normal lung tissue from a non-PAP patient. The iron inside alveolar macrophages was stained with Berlin blue, and its distribution was compared with that on micro-PIXE images.Results: The elements composing particles and their locations in the PAP specimens could be identified by in-air micro-PIXE analysis, with magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), scandium (Sc), potassium (K), calcium (Ca), titanium (Ti), chromium (Cr), copper (Cu), manganase (Mn), iron (Fe), and zinc (Zn) being detected. Si was the major component of the particles. Serial sections stained by Berlin blue revealed accumulation of sideromacrophages that had phagocytosed the particles. The intracellular iron content of alveolar macrophage from the surfactant-rich area in PAP was higher than normal lung tissue in control lung by both in-air micro-PIXE analysis and Berlin blue staining.Conclusion: The present study demonstrated the efficacy of in-air micro-PIXE for analyzing the distribution and composition of lung particles. The intracellular iron content of single cells was determined by simultaneous two-dimensional and elemental analysis of paraffin-embedded lung tissue sections. The results suggest that secondary PAP is associated with exposure to inhaled particles and accumulation of iron in alveolar macrophages. [ABSTRACT FROM AUTHOR]

The Adacolumn is an adsorptive-type extracorporeal device, which is filled with cellulose diacetate beads that selectively adsorb granulocytes and monocytes. Patients with severe persistent asthma experience highly variable continuous symptoms and severe exacerbations in spite of medication based on inhaled glucocorticosteroids. Granulocyte and monocyte adsorption apheresis using extracorporeal circulation through the Adacolumn was performed in nine patients with severe persistent asthma. The extracorporeal circulation through the Adacolumn was performed once a week for 5 weeks. We were able to perform this therapy without any severe adverse effects in all patients, although one patient complained of general fatigue just after the circulations. In six of the nine patients, the increase in peak expiratory flow (PEF) was more than 50 mL/min. The average increase in morning PEF was 23.3% while that in the evening PEF was 26.4% after the therapy. This therapy was not harmful for patients with severe persistent asthma. A placebo-controlled study will be desired to evaluate the efficacy of this nonpharmacological strategy accurately. [ABSTRACT FROM AUTHOR]

Most studies on the frequency of autism have had methodological problems. Most notable of these have been differences in diagnostic criteria between studies, degree of cases overlooked by the initial screening, and type of measurement. This study aimed to replicate the first report on childhood autism to address cumulative incidence as well as prevalence, as defined in the International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10) Diagnostic Criteria for Research. Here, the same methodological accuracy (exactness of a measurement to the true value) as the first study was used, but population size was four times larger to achieve greater precision (reduction of random error). A community-oriented system of early detection and early intervention for developmental disorders was established in the northern part of Yokohama, Japan. The city's routine health checkup for 18-month-old children served as the initial mass screening, and all facilities that provided child care services aimed to detect all cases of childhood autism and refer them to the Yokohama Rehabilitation Center. Cumulative incidence up to age 5 years was calculated for childhood autism among a birth cohort from four successive years (1988 to 1991). Cumulative incidence of childhood autism was 27.2 per 10 000. Cumulative incidences by sex were 38.4 per 10 000 in males, and 15.5 per 10 000 in females. The male:female ratio was 2.5:1. The proportions of children with high-functioning autism who had Binet IQs of 70 and over and those with Binet IQs of 85 and over were 25.3% and 13.7% respectively. Data on cumulative incidence of childhood autism derived from this study are the first to be drawn from an accurate, as well as precise, screening methodology. [ABSTRACT FROM AUTHOR]

Direct bonding of diamond and Cu was successfully conducted by the surface activated bonding method at room temperature. The structure of the diamond/Cu bonding interface was investigated by transmission electron microscopy and electron energy-loss spectroscopy. The effect of heat treatment temperature on the interface structure was also investigated. A 4-nm-thick damaged layer was formed at the as-bonded interface, and the damaged layer's thickness decreased with an annealing temperature rise. It was found that the atomic ratio of sp2 bonding in the bonding interface was larger than that of the diamond separated from the interface by approximately 50 nm, which indicates that the damaged layer was composed of amorphous carbon or graphite and diamond. After annealing at 700 °C, a composite layer about 2 nm thick was observed at the interface. There were no nano-voids or micro-cracks observed at the interface with annealing at a temperature as high as 700 °C. These results indicate that the diamond/Cu bonding interface has high thermal stability and can withstand the temperature rise of power devices during operation. [ABSTRACT FROM AUTHOR]

We have shown that the structural and compositional properties of semiconductor interfaces fabricated by surface activated bonding (SAB) would be modified during focused ion beam (FIB) processes operated at room temperature (RT), especially for wide band-gap materials, and such a modification can be suppressed by FIB processes operated at lower temperatures. During FIB processes operated at RT, SAB-fabricated Si/Si and GaAs/GaAs interfaces are amorphized along the interfaces, even at the internal locations deeper than the penetration depth of the FIB, and the impurity distribution across the interfaces is modified. This phenomenon is presumably due to the atomic diffusion assisted by the point defects that are introduced by FIB irradiation. By using FIB processes operated at −150 °C, the FIB-induced atomic diffusion would be ignored for Si/Si interfaces. Meanwhile, the diffusion would be still effective for GaAs/GaAs interfaces, presumably due to the effects of recombination-enhanced defect motion under FIB irradiation. [ABSTRACT FROM AUTHOR]

The effect of P or B predoping on As diffusion in polycrystalline Si was investigated by atom probe tomography. In all samples, a high concentration of As was found at grain boundaries, indicating that such boundaries are the main diffusion path. However, As grain-boundary diffusion was suppressed in the B-doped sample and enhanced in the P-doped sample. In a sample codoped with both P and B, As diffusion was somewhat enhanced, indicating competition between the effects of the two dopants. The results suggest that As grain-boundary diffusion can be controlled by varying the local concentration of P or B. [ABSTRACT FROM AUTHOR]

The successful formation of abrupt phosphorus (P) δ-doping profiles in germanium (Ge) is reported. When the P δ-doping layers were grown by molecular beam epitaxy (MBE) directly on Ge wafers whose surfaces had residual carbon impurities, more than a half the phosphorus atoms were confined successfully within a few nm of the initial doping position even after the growth of Ge capping layers on the top. On the other hand, the same P layers grown on Ge buffer layers that had much less carbon showed significantly broadened P concentration profiles. Current–voltage characteristics of Au/Ti/Ge capping/P δ-doping/n-Ge structures having the abrupt P δ-doping layers with carbon assistance showed excellent ohmic behaviors when P doses were higher than 1 × 1014 cm−2 and the capping layer thickness was as thin as 5 nm. Therefore, the insertion of carbon around the P doping layer is a useful way of realizing ultrashallow junctions in Ge. [ABSTRACT FROM AUTHOR]

The impact of carbon (C) co-implantation on boron (B) activation in crystalline silicon was investigated. The detailed distribution of B and C atoms and B activation ratios dependent on the C ion-implantation energies were examined based on three-dimensional spatial mappings of B and C obtained by atom probe tomography and from depth profiles of their concentrations from secondary ion mass spectrometry and depth profiles of carrier concentrations with spreading resistance measurements. At all C implantation energies (8, 15, and 30 keV), B out-diffusion during activation annealing was reduced, so that more B atoms were observed in the C co-implanted samples. The carrier concentration was decreased throughout the entire implanted region for C implantation energies of 15 and 30 keV, although it was only increased at greater depths for C co-implantation at 8 keV. Two different effects of C co-implantation, (I) reduction of B out-diffusion and (II) influence of B activation, were confirmed. [ABSTRACT FROM AUTHOR]