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(Ba,Sr)(Co,Fe)O3−δ based mixed conducting oxides, e.g. (Ba0.5Sr0.5)(Co1−xFex)O3−δ and Ba(Co0.7Fe0.3−xNbx)O3−δ, are promising candidates for oxygen permeable membranes and SOFC cathodes due to their excellent ambipolar conductivities. Despite these excellent properties, however, their mass/charge transport properties have not been fully characterized and hence, their defect structure has not been clearly elucidated. Until now, the majority types of ionic and electronic defects have been regarded as oxygen vacancies and localized holes. Holes, whether localized or not, are acceptable as majority electronic carriers on the basis of the as-measured total conductivity, which is essentially electronic, and electronic thermopower. On the other hand, the proposal of oxygen vacancies as majority ionic carriers lacks solid evidence. In this work, we document all the isothermal transport properties of Ba(Co0.70Fe0.22Nb0.08)O3−δ in terms of a 2 × 2 Onsager transport coefficient matrix and its steady-state electronic thermopower against oxygen activity at elevated temperatures, and determine the valences of Co and Fe via soft X-ray absorption spectroscopy. It turns out that the ionic and electronic defects in majority should be oxygen interstitials and at least two kinds of holes, one free and the other trapped. Furthermore, the lattice molecule should be Ba(Co0.7Fe0.3−xNbx)O2+δ, not Ba(Co0.7Fe0.3−xNbx)O3−δ, to be consistent with all the results observed. [ABSTRACT FROM AUTHOR]

Abstract: BaCo0.70Fe0.22Nb0.08O3−δ (BCFN) is known to be one of state-of-the-art materials for oxygen permeation membranes, but its partial conductivities governing the oxygen permeability are still yet to be characterized. We have established, by an electrochemical polarization method under the ion-blocking condition, the Onsager transport coefficient matrix L mn such that J m =−L mn∇η n, where J m and ∇η n are the flux and electrochemical potential gradients of charge carriers (m, n=oxide ions O2−, holes h+), respectively, and thereby derived its partial ionic and electronic conductivities as functions of oxygen activity in the range of −5< <0 at 750°C, 850°C, and 950°C, respectively. It has been found that the oxide ionic conductivity is on the order of 1S/cm with the ionic transference number of the order of 0.1; furthermore, the cross coefficient L mn(m≠n) or ion–electron interference upon their transfer is appreciable in the entire ranges examined. The oxygen permeation flux is finally calculated as a function of the sweep-side oxygen activity at the three temperatures and compared with the experimental values available. [Copyright &y& Elsevier]

Abstract: Partial electronic conductivity and total conductivity have been determined by Hebb–Wagner polarization method and a.c. impedance spectroscopy, respectively, on bilayer electrolyte Zr0.84Y0.16O1.92(YSZ)/Ce0.9Gd0.1O1.95(GDC) with thickness ratios 10−3/1 and 10−4/1 at 800°, 900° and 1000°C, respectively. While their ionic conductivities remain close to that of GDC, the electronic conductivities are suppressed the more from that of GDC towards that of YSZ the higher the thickness ratio, as expected. Even when the GDC-side is exposed to reducing atmosphere, the electronic conductivity is also suppressed, but to a less extent. It is suggested that oxygen activity distribution is discontinuous across the YSZ/GDC interface under ion-blocking condition, refuting the “continuity hypothesis” that has been usually adopted in calculating the oxygen activity distribution across a multilayer of mixed conductor oxides. The electrolytic domain widths of the bilayer electrolyte are reported depending on temperature, thickness ratio and direction of oxygen activity gradient imposed. [Copyright &y& Elsevier]

Abstract: Usnic acid is a lichen metabolite used as a weight-loss dietary supplement due to its uncoupling action on mitochondria. However, its use has been associated with severe liver disorders in some individuals. Animal studies conducted thus far evaluated the effects of usnic acid on mitochondria primarily by measuring the rate of oxygen consumption and/or ATP generation. To obtain further insight into usnic acid-mediated effects on mitochondria, we examined the expression levels of 542 genes associated with mitochondrial structure and functions in liver of B6C3F1 female mice using a mitochondria-specific microarray. Beginning at 8weeks of age, mice received usnic acid at 0, 60, 180, and 600ppm in ground, irradiated 5LG6 diet for 14days. Microarray analysis showed a significant effect of usnic acid on the expression of several genes only at the highest dose of 600ppm. A prominent finding of the study was a significant induction of genes associated with complexes I through IV of the electron transport chain. Moreover, several genes involved in fatty acid oxidation, the Krebs cycle, apoptosis, and membrane transporters were over-expressed. Usnic acid is a lipophilic weak acid that can diffuse through mitochondrial membranes and cause a proton leak (uncoupling). The up-regulation of complexes I–IV may be a compensatory mechanism to maintain the proton gradient across the mitochondrial inner membrane. In addition, induction of fatty acid oxidation and the Krebs cycle may be an adaptive response to uncoupling of mitochondria. [Copyright &y& Elsevier]

Abstract: Li–B–P–O containing oxide nano-particles were synthesized from BCl3, POCl3 gases and an aqueous LiNO3 by flame hydrolysis reaction. Li2O–B2O3–P2O5 thin-film electrolyte was fabricated from as-deposited oxide particles by sintering at various temperatures between 500 and 600°C. The effect of the sintering temperature on vitrification and electrical conductivity was investigated to find the optimum condition for the fabrication of thin-film electrolyte. Raman spectra and DTA measurement revealed that the crystalline H3BO3 impurity phase was included in the as-deposited film and was converted to glass former B2O3 during heat treatment above 550°C. Raman spectra also indicate that the non-bridging oxygens within glass network increased with the vitrification at the elevated temperature. Accordingly, the conductivity of electrolyte was increased with increasing sintering temperature. However, in the ambient atmosphere, the diborate groups with non-bridging in glass electrolyte slowly transformed to H3BO3 again by reaction with moisture. [Copyright &y& Elsevier]

Abstract: Crystalline LiCoO2 nano-powders for lithium-ion battery were synthesized by aerosol flame deposition (AFD). The aqueous precursor solution was atomized with an ultrasonic vibrator and supplied to the oxy-hydrogen flame by flowing dry Ar gas. The as-deposited soot powders were collected on a substrate placed on a heating stage. X-ray diffraction and transmission electron microscopy (TEM) show that the soot powders were composed of nano-sized particles of Li2CO3, CoCo3 and Co3O4 and the subsequent heat treatments at 700°C for 5h that converted these powders to well-layered LiCoO2 powder. The flow rate of H2 flame gas was discovered to have influenced the phase composition in the as-deposited soot. The electrochemical performance of synthesized nano-powders was investigated using 2032 coin-type cell. LiCoO2 nano-powder synthesized at an H2 flow rate of 2.5l/min sintered at 700°C for 5h showed a first discharge capacity of 144mAh/g and good rechargeability in Li//1M LiPF6-EC/DEC//LiCoO2 cells between 3 and 4.3V. [Copyright &y& Elsevier]

Abstract: Crystalline LiCoO2 nano-particles for thin film battery were synthesized and deposited by aerosol flame deposition (AFD). The aqueous precursor solution of the lithium nitrate and cobalt acetate was atomized with an ultrasonic vibrator and subsequently carried into the central tube of the torch by flowing dry Ar gas. LiCoO2 were formed by oxy-hydrogen flame and deposited on a substrate placed in a heating stage. The deposited soot film composed of nano-sized particles was subsequently consolidated into a dense film by high temperature heat treatment at 500–800°C for 5h and characterized by SEM, XRD, and Raman spectroscopy. The crystalline carbonates and oxide were first formed by the deposition and the subsequent heat treatment converted those to LiCoO2. The FWHMs of the XRD peaks were reduced and their intensity increased as the heat treatment temperature increased, which is due to improved crystallinity. When judged from the low enough cation mixing and well-developed layered structure, it is believed that the LiCoO2 film satisfied the quality standard for the real application. SEM measurements showed that LiCoO2 were nano-crystalline structure with the average particle size <70nm and the particle size increased with the increase of heat treatment temperature. The thickness of thin film LiCoO2 before the consolidation process was about 15μm and reduced to about 4μm after sintering. [Copyright &y& Elsevier]

Geothermal source heat pump (GSHP) systems as renewable energy systems are being more frequently installed as part of the zero-energy building drive. However, in South Korea, where a large amount of heating load can be required, maintaining high system performance by using only a GSHP is difficult owing to the gradual degradation of its thermal performance. The performance of a solar-assisted GSHP system was therefore experimentally analyzed and compared with a GSHP-only system. The results showed that the heating coefficient of performance of the GSHP-only operation was 5.4, while that of the solar-assisted GSHP operation was 7.0. In the case of the GSHP-only system, the maximum temperature of the heat pump water supply on the heat source side was initially 13.1 °C, but this rapidly decreased to 11.4 °C during operation. For the solar-assisted GSHP system, the temperature of the water supply to the heat source side of the heat pump was controlled at 15–20.9 °C, and the power consumption for system operation was reduced by about 20% compared with that for the GSHP-only system. Much higher temperatures could be supplied when solar heat is used instead of ground heat, as solar heat contributes to the performance improvement of the heat pump system. [ABSTRACT FROM AUTHOR]

We have previously shown that Listeria monocytogenes , a causative agent of listeriosis, can produce membrane vesicles (MVs) during in vitro culture. The aim of this study was to investigate the ability of MVs from L. monocytogenes cultured with or without salt stress to induce cytotoxicity and pro-inflammatory responses in colon epithelial Caco-2 cells. MVs were purified from wild-type L. monocytogenes 10403S strain and an isogenic Δ sigB mutant strain. MVs from both wild-type and Δ sigB mutant strains increased viability of Caco-2 cells regardless of salt stress. Both MVs from wild-type and Δ sigB mutant strains stimulated expression of pro-inflammatory cytokine and chemokine genes in Caco-2 cells. Expression levels of pro-inflammatory cytokine genes in cells treated with MVs from bacteria cultured without salt stress were significantly higher than those in cells treated with MVs from bacteria cultured with salt stress. However, expression levels of chemokine genes in cells treated with MVs from bacteria cultured with salt stress were significantly higher than those in cells treated with MVs from bacteria cultured without salt stress. In addition, expression levels of interleukin (IL)-1β and IL-8 genes were partially inhibited by either lysozyme-treated MVs or ethylenediaminetetraacetic acid-treated MVs compared to those after treatment with intact MVs. Our results suggest that salt stress can affect the production of L. monocytogenes MVs, thus causing different pro-inflammatory responses in host cells. • MVs from L. monocytogenes are not cytotoxic to epithelial cells. • MVs from salt stressed L. monocytogenes induce different inflammatory responses. • Intact MVs can enhance pro-inflammatory responses. [ABSTRACT FROM AUTHOR]

Innate immune training involves myelopoiesis, dynamic gene modulation, and functional reprogramming of myeloid cells in response to secondary heterologous challenges. The present study evaluates whether systemic innate immune training can protect tissues from local injury. Systemic pretreatment of mice with β‐glucan, a trained immunity agonist, reduces the mortality rate of mice with bleomycin‐induced lung injury and fibrosis, as well as decreasing collagen deposition in the lungs. β‐Glucan pretreatment induces neutrophil accumulation in the lungs and enhances efferocytosis. Training of mice with β‐glucan results in histone modification in both alveolar macrophages (AMs) and neighboring lung epithelial cells. Training also increases the production of RvD1 and soluble mediators by AMs and efferocytes. Efferocytosis increases trained immunity in AMs by stimulating RvD1 release, thus inducing SIRT1 expression in neighboring lung epithelial cells. Elevated epithelial SIRT1 expression is associated with decreased epithelial cell apoptosis after lung injury, attenuating tissue damage. Further, neutrophil depletion dampens the effects of β‐glucan on macrophage accumulation, epigenetic modification in lung macrophages, epithelial SIRT1 expression, and injury‐mediated fibrosis in the lung. These findings provide mechanistic insights into innate immune training and clues to the potential ability of centrally trained immunity to protect peripheral organs against injury‐mediated disorders. [ABSTRACT FROM AUTHOR]

Dental CBCT and panoramic images are important imaging modalities used in dental diagnosis and treatment planning. In order to acquire a panoramic image without an additional panoramic scan, in this study, we proposed a method of reconstructing a panoramic image by extracting panoramic projection data from dental CBCT projection data. After specifying the patient's dental arch from the patient's CBCT image, panoramic projection data are extracted from the CBCT projection data along the appropriate panoramic scan trajectory that fits the dental arch. A total of 40 clinical human datasets and one head phantom dataset were used to test the proposed method. The clinical human dataset used in this study includes cases in which it is difficult to reconstruct panoramic images from CBCT images, such as data with severe metal artifacts or data without teeth. As a result of applying the panoramic image reconstruction method proposed in this study, we were able to successfully acquire panoramic images from the CBCT projection data of various patients. The proposed method acquires a universally applicable panoramic image that is less affected by CBCT image quality and metal artifacts by extracting panoramic projection data from dental CBCT data and reconstructing a panoramic image. [ABSTRACT FROM AUTHOR]

Gram-negative bacteria produce extracellular outer membrane vesicles (OMVs) that interact with host cells. Unlike Gram-negative bacteria, less is known about the production and role of extracellular membrane vesicles (MVs) in Gram-positive bacteria. The food-borne pathogen Listeria monocytogenes can survive under extreme environmental and energy stress conditions and the transcription factor σB is involved in this survival ability. Here, we first determined the production of MVs from L. monocytogenes and evaluated whether general stress transcription factor σB affected production of MVs in L. monocytogenes. L. monocytogenes secreted MVs during in vitro broth culture. The wild-type strain actively produced MVs approximately nine times more and also produced more intact shapes of MVs than those of the isogenic ΔsigB mutant. A proteomic analysis showed that 130 and 89 MV proteins were identified in the wild-type and ΔsigB mutant strains, respectively. Wild-type strain-derived MVs contained proteins regulated by σB such as transporters (OpuCA and OpuCC), stress response (Kat), metabolism (LacD), translation (InfC), and cell division protein (FtsZ). Gene Ontology (GO) enrichment analysis showed that wild-type-derived MV proteins corresponded to several GO terms, including response to stress (heat, acid, and bile resistance) and extracellular polysaccharide biosynthetic process, but not the ΔsigB mutant. Internalin B (InlB) was almost three times more contained in MVs derived from the wild-type strain than in MVs derived from the ΔsigB mutant. Taken together, these results suggest that σB plays a pivotal role in the production of MVs and protein profiles contained in MVs. L. monocytogenes MVs may contribute to host infection and survival ability under various stressful conditions. [ABSTRACT FROM AUTHOR]