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The surface treatment for a polymer‐ceramic composite is additionally performed in advanced material industries. To prepare the composite without a surface treatment, the simplest way to manufacture an advanced ceramic‐particle is devised. The method is the formation of a nanocrystalline composite layer through the simple liquid‐phase sintering. Using magnesia (MgO) which shows hydrophilicity, a nanocrystalline surface layer is realized by liquid‐phase sintering. The amorphous matrix of nanocrystalline composite layer makes MgO hydrophobic and ensures miscibility with polymers, and the nanocrystalline MgO ensures high thermal conductivity. In addition, the liquid phase removes the open pores and makes the surface morphology smooth MgO with smooth surface (MgO‐SM). Thermal interface materials (TIM) prepared with MgO‐SM and epoxy show a high thermal conductivity of ≈7.5 W m−1K−1, which is significantly higher than 4.5 W m−1K−1 of pure MgO TIM. Consequently, the formation process of a nanocrystalline surface layer utilizing simple liquid‐phase sintering is proposed as a fabrication method for a next‐generation ceramic‐filler. In addition, it is fundamentally identified that the thermal conductivity of MgO depends on the Mg deficiency, and therefore a poly‐crystal MgO‐SM (produced at a low temperature) has a higher thermal conductivity than a single‐crystal MgO (produced at a high temperature). [ABSTRACT FROM AUTHOR]

Background: The cross‐linked hyaluronic acid (HA) fillers are the viscoelastic hydrogel with a dominant elasticity rather than a viscosity as a useful medical device in the soft tissue augmentation. These HA fillers undergo deformation to begin the biodegradation by the biochemical and physical environment of the body, and result of deformations are closely related to clinical performance. Aims: The specific equation of molding index is newly generated and proved with Collin's equation, which is used for strong elastomers, for selecting optimal product in facial treatment. Methods: In this study, the results of amplitude sweep test from five marketed HA fillers were mathematically demonstrated for the proper clinical application. Results: The increment of loss modulus by deformation was evaluated as a useful factor for the maintenance of optimal shape molding performance and resistance to external deformation of the cross‐linked HA gel. From this study, the equation of molding index for weak viscoelastic hydrogels like HA products can be applied for choosing which products even in aesthetic plastic field. This molding index equation is compared to Collins' equation that index of deformation as elastomer like rubber and then found the positive correlation between two equations. Conclusion: This study could provide a basic theory that achieve useful clinical performance according to characteristics among many types of medical devices based on the molding index. [ABSTRACT FROM AUTHOR]

Anode‐free lithium metal batteries (AFLMBs) show promise as a means of further enhancing the energy density of current lithium‐ion batteries, as they do not require conventional graphite anodes. The anode‐free configuration, however, suffers from inferior chemical stability of the solid electrolyte interphase (SEI) layer and experiences inhomogeneous lithium deposition during charge/discharge processes, resulting in rapid capacity fading. To address these issues, a carbonized polydopamine (CPD) coating is applied to the copper current collector. The CPD‐coated copper current collector promotes highly efficient and reversible lithium plating and stripping processes, resulting in a densely packed lithium deposition that significantly improves cycling stability. The anode‐free full cell, consisting of CPD‐coated copper current collector and a LiFePO4 cathode, demonstrates significantly improved electrochemical performance, with a capacity retention of more than 63% after 100 cycles at a current rate of 0.3C. The stability of the SEI layer and the presence of lithiophilic sites are verified through a range of techniques, including optical microscopy, Raman spectroscopy, X‐ray photoelectron spectroscopy, chronoamperometry, and electrochemical impedance spectroscopy. Based on these collective findings, it can be inferred that the use of CPD coating provides a simple way to enhance the electrochemical performance of AFLMBs. [ABSTRACT FROM AUTHOR]

This study suggests approaches to achieve the desired size and size distribution of highly dense spherical granules by investigating the effect of slurry conditions on size distribution. Highly dense spherical granules were prepared with a solid content of over 77 wt% by spray‐drying the slurry. A prolonged deagglomeration time of 64 h provided adequate flowing ability by breaking up almost all aggregates and improved dispersibility, resulting in reduced granule sizes and narrow size distributions. The optimum slurry conditions for maintaining dispersibility were 1 wt% of the dispersant and a strong basic pH, which had the greatest effect on size distribution. Based on these considerations, the 10.6 µm sized 3 mol% yttria‐stabilized zirconia granules were synthesized with 99.83% density, 97.17% sphericity, and uniform size with fraction yield of 80.01% at 10–20 µm. These dense granules have significantly higher hardness and modulus values of 19.19 and 206.68 GPa, respectively, than that of pellet and film types. To the best of our knowledge, the relationship between the slurries and the span of the size distribution of ceramic granules during spray‐drying has been demonstrated for the first time. [ABSTRACT FROM AUTHOR]

Streptomyces are important industrial bacteria that produce pharmaceutically valuable polyketides. However, mass production on an industrial scale is limited by low productivity, which can be overcome through metabolic engineering and the synthetic biology of the host strain. Recently, the introduction of an auto‐inducible expression system depending on microbial physiological state has been suggested as an important tool for the industrial‐scale production of polyketides. In this study, titer improvement by enhancing the pool of CoA‐derived precursors required for polyketide production was driven in a quorum sensing (QS)‐dependent manner. A self‐sustaining and inducer‐independent regulatory system, named the QS‐based metabolic engineering of precursor pool (QMP) system, was constructed, wherein the expression of genes involved in precursor biosynthesis was regulated by the QS‐responsive promoter, scbAp. The QMP system was applied for neoaureothin production in a heterologous host, Streptomyces coelicolor M1152, and productivity increased by up to 4‐fold. In particular, the engineered hyperproducers produced high levels of neoaureothin without adversely affecting cell growth. Overall, this study showed that self‐regulated metabolic engineering mediated by QS has the potential to engineer strains for polyketide titer improvement. [ABSTRACT FROM AUTHOR]

Aim: The physiological effects and cellular mechanism of 25‐hydroxycholesterol (25‐HC), which is an oxysterol synthesized from cholesterol by cholesterol‐25‐hydroxylase (CH25H) expressed under inflammatory conditions, are still largely unknown during odontoclastogenesis. This study aimed to evaluate 25‐HC‐induced odontoclastogenesis and its cellular mechanisms in odontoblast‐like MDPC‐23 cells. Methodology: To investigate 25‐HC‐induced odontoclastogenesis of MDPC‐23 cells and its cellular mechanism, haemotoxylin and eosin staining, tartrate‐resistant acid phosphatase (TRAP) staining, dentine resorption assay, zymography, reactive oxygen species (ROS) detection, immunocytochemistry, and nuclear translocation were performed. The experimental values are presented as mean ± standard deviation and were compared using analysis of variance, followed by post hoc multiple comparisons (Tukey's test) using SPSS software version 22 (IBM Corp.). A p‐value <.05 was considered statistically significant. Results: Lipopolysaccharide or receptor activator of nuclear factor‐κB ligand (RANKL) induced the synthesis of 25‐HC via the expression of CH25H in MDPC‐23 cells (p <.01). Multinucleated giant cells with morphological characteristics and TRAP activity of the odontoclast were increased by 25‐HC in MDPC‐23 cells (p <.01). Moreover, 25‐HC increased dentine resorption through the expression and activity of matrix metalloproteinases in MDPC‐23 cells. It not only increased the expression of odontoclastogenic biomarkers but also translocated cytosolic nuclear factor‐κB (NF‐κB) to the nucleus in MDPC‐23 cells. Additionally, 25‐HC not only increased the production of ROS (p <.01), expression of inflammatory mediators (p <.01), pro‐inflammatory cytokines, receptor activator of NF‐κB (RANK), and RANKL but also suppressed the expression of osteoprotegerin (OPG) in MDPC‐23 cells. In contrast, CDDO‐Me, a chemical NF‐κB inhibitor, decreased TRAP activity (p <.01) and downregulated the expression of the odontoclastogenic biomarkers, including RANK and RANKL, in MDPC‐23 cells. Conclusion: 25‐HC induced odontoclastogenesis by modulating the RANK–RANKL–OPG axis via NF‐κB activation in MDPC‐23 cells. Therefore, these findings provide that 25‐HC derived from cholesterol metabolism may be involved in the pathophysiological etiological factors of internal tooth resorption. [ABSTRACT FROM AUTHOR]

Overall, 8‐mol% yttria‐stabilized zirconia (8YSZ), unlike 3YSZ, is optically transparent and stable against low‐temperature degradation but has insufficient mechanical properties due to its large grain size. The influence of the grain size of 8YSZ on mechanical properties was investigated to develop an 8YSZ suitable for dental restoration. Modulation of the grain size and relative density was achieved via a two‐step sintering (TSS) process, and the corresponding kinetic window was established. The conditions of TSS employed herein yielded a relative density of more than 99% while maintaining a small grain size of 0.75 µm. On the other hand, the highest biaxial strength and the highest total transmittance attained were 833 MPa and 34.6% (1‐mm‐ thick, 39.1% for a 0.5‐mm thick sample) in the TSS 8YSZ with a grain size of 1.25 µm. These results suggest that strength has improved only when grain size reduction and increased relative density are achieved at the same time. The results demonstrate that the ceramic processing method has a significant effect on the mechanical and optical properties of 8YSZ needed for dental restoration and provide a new insight that contrasts previous studies focused on the starting material. [ABSTRACT FROM AUTHOR]

Background: Serum testosterone assays are an important tool in the clinical evaluation of a number of endocrine disorders including male hypogonadism. However, serum testosterone has a limited role in real clinical use due to its inaccuracy. We aimed to assess the association between prostate‐specific antigen (PSA) and testosterone as well as the effects of various types of testosterone replacement therapy (TRT) for PSA level. Methods: Two electronic databases were screened: PubMed (1966 through December 2018) and Cochrane Library (1993 through December 2018). The first strategy compared the overall increase in PSA following testosterone treatment compared with placebo. The second strategy analyzed the overall association between PSA and testosterone among the observational studies. Results: In the first strategy, 22 articles were included in the final analysis. In the second strategy, 18 studies were included. Testosterone replacement therapy (TRT) showed a significant change in PSA level compared to that in the placebo group (mean difference [MD]: 0.13, 95% CI: 0.01‐0.25, P =.04). Compared to placebo, only intramuscular (IM) TRT shows a significant change in PSA level group (MD: 0.16, 95% CI: 0.01‐0.30, P =.04), as neither the oral nor topical type showed a significant change in PSA. In the second strategy analysis, there was no overall correlation found between PSA and testosterone (z = 0.04, 95% CI: −0.04 to 0.12, P =.04; r = 0.039). However, in the subgroup of non‐BPH (benign prostate hyperplasia), a significant correlation between PSA and testosterone (z = 0.07, 95% CI: 0.01‐0.13, P =.009; r = 0.089) was found. Conclusions: We found that TRT, particularly IM TRT, significantly changed the PSA level compared with the placebo group. Furthermore, there was a significant correlation between PSA and testosterone in patients with non‐BPH. According to these findings, we suggest the possibility of PSA as a surrogate marker of testosterone. [ABSTRACT FROM AUTHOR]

A method for the separation and quantification of acteoside by reverse-phase high-performance liquid chromatography (HPLC) was developed and validated. Hot water and ethanolic extracts of Osmanthus fragrans leaves and flowers were analyzed for acteoside content. Excellent linearity was obtained, with an r2 higher than 0.999. The precision, specificity, and accuracy of our method were excellent, suggesting that it can be conveniently used for the quantification of acteoside in the crude extract of O. fragrans. The hot water and ethanol extracts were analyzed, and their biological activities were tested. The extraction yields, marker (acteoside) contents, and antioxidant activities of the leaf and flower extracts were analyzed. The antioxidant activity was confirmed by measuring the 2,2-diphenyl-2-picrylhydrazyl radical scavenging activity, reducing power, and total phenolic content. The acteoside content tended to be higher in the 100% ethanol extract of O. fragrans compared to those with the other extraction conditions tested. Overall, almost all extracts prepared with ethanolic solvents tended to produce better antioxidant activity than those prepared with hot water. These results suggest that the ethanolic extract of O. fragrans could serve as a potential antioxidant and anti-inflammatory pharmaceutical source, and our validated method would be useful for the quality control of O. fragrans extracts. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is characterized by relapsing pruritus and skin dryness. Due to the pathogenic multiplicity and the adverse effects associated with the current therapeutics, development of transdermal drug delivery system is becoming an area of interest. Here, a novel topical film prepared with Rhus verniciflua extract (RVE)‐loaded pullulan hydrogel (RVE@PH) was synthesized and tested its therapeutic efficacy on the AD rats modeled by neonatal capsaicin injection method. The RVE@PH was characterized by a Fourier‐transform infrared spectroscopy and an in vitro release assay. Rat pups were randomly divided into two groups: vehicle‐treated (VEH; n = 5) and capsaicin‐treated (n = 15). The latter were given capsaicin subcutaneously at 24 h after birth for AD induction and further divided into three groups (n = 5 per each): not treated (CAP), pullulan hydrogel‐applied (PH), and RVE@PH‐applied (RVE‐PH). The pullulan hydrogel and RVE@PH were topically applied on shoulder lesions for 14 days (from 42 to 56 days after birth). Their phenotypes were compared based on the dermatitis score, epidermal thickness, mast cell infiltration, and serum myeloperoxidase (MPO) activities. The PH group showed significant attenuation in all the aforementioned values compared to the CAP group, suggesting that pullulan hydrogel itself has therapeutic activity against AD. Notably, the attenuations were more potent in the RVE‐PH group than the PH group, indicating that the therapeutic efficacy against AD is augmented by the presence of RVE, a loaded pharmaceutic. Collectively, these results indicate that RVE@PH inhibits AD through exerting the dual roles, that is, the pullulan hydrogel‐mediated physical and RVE‐mediated pharmaceutical actions. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 2325–2334, 2019. [ABSTRACT FROM AUTHOR]

Since concentrated electrolytes have attracted great attention for the stabilization of lithium‐metal anodes for lithium‐ion batteries, the demonstration of a full cell with an electrolyte concentration study has become a research topic of interest. Herein, we have demonstrated a proof of concept, a lithium–polysulfide full cell battery using various lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) electrolyte concentrations with glass‐fiber‐based composite and hard carbon as the cathode and anode, respectively. The initial capacity of the lithium‐polysulfide full cell is found to be 970 mA h g−1 at 0.1 C. The capacity is stabilized at 870 mA h g−1 after 100 cycles with a capacity retention of 88.6 %. An excellent capacity retention of ≈80 % is achieved after long 800 cycles at 0.5 C by using full cell technology. Further, our post‐mortem analysis sheds light on the difference in SEI layer formation on hard carbon anodes with changing electrolyte concentration, thereby indicating reasons for the obtainment of a high cyclic performance with 1 m LiTFSI salt electrolyte. The successful demonstration of the long cyclic performance of Li–polysulfide full cells is indeed a step towards producing high performance Li–polysulfide full cell batteries with long cycling using conventional LiTFSI salt electrolyte and commercial anode materials. Stable progress: Introducing carbon as an anode dramatically stabilized the Li–polysulfide battery powered full‐cell performance with a high initial capacity of 970 mA h g−1 at 0.1 C compared to the low capacity achieved in half cells. The successful demonstration of the long cyclic performance is indeed a step towards producing high performance Li–polysulfide full cell batteries with long cycling using a conventional salt electrolyte and commercial anode materials. [ABSTRACT FROM AUTHOR]

Abstract: Sodium ion batteries (NIBs) have become attractive promising alternatives to lithium ion batteries in a broad field of future energy storage applications. The development of high‐performance anode materials has become an essential factor and a great challenge toward satisfying the requirements for NIBs, advancement. This work is the first report on GeS2 nanocomposites uniformly distributed on reduced graphene oxide (rGO) as promising anode materials for NIBs prepared via a facile hydrothermal synthesis and a unique carbo‐thermal annealing. The results show that the GeS2/rGO hybrid anode yields a high reversible specific capacity of 805 mA h g−1 beyond the theoretical capacity, an excellent rate capability of 616 mA h g−1 at 5 A g−1, and a cycle retention of 89.4% after 100 cycles. A combined ex situ characterization study reveals that the electrochemically driven amorphization plays a key role in achieving efficient sodium storage by accommodating excess sodium ions in the electrode materials. Understanding the sequential conversion‐alloying reaction mechanism for GeS2/rGO hybrid anodes provides a new approach for developing high‐performance energy storage applications. [ABSTRACT FROM AUTHOR]

Hybrid capacitors, especially sodium hybrid capacitors (NHCs), have continued to gain importance and are extensively studied based on their excellent potential to serve as advanced devices for fulfilling high energy and high power requirements at a low cost. To achieve remarkable performance in hybrid capacitors, the two electrodes employed must be superior with enhanced charge storage capability and fast kinetics. In this study, a new sodium hybrid capacitor system with a sodium super ionic conductor NaTi2(PO4)3 grown on graphene nanosheets as an intercalation electrode and 2D graphene nanosheets as an adsorption electrode is reported for the first time. This new system delivers a high energy density of ≈80 W h kg−1 and a high specific power of 8 kW kg−1. An ultralow performance fading of ≈0.13% per 1000 cycles (90%-75 000 cycles) outperforms previously reported sodium ion capacitors. The enhanced charge transfer kinetics and reduced interfacial resistance at high current rates deliver a high specific energy without compromising the high specific power along with high durability, and thereby bridge batteries and capacitors. This new research on kinetically enhanced NHCs can be a trendsetter for the development of advanced energy storage devices requiring high energy-high power. [ABSTRACT FROM AUTHOR]

Highly sinterable powders are required for the fabrication of transparent ceramics. Here, we studied the effects of calcination atmosphere on the characteristics of monodispersed spherical Y2O3 powders, such as crystallite size and particle density, for high optical transparent ceramics. It was found that vacuum calcination around the crystallization temperature is the crucial step to eliminate intragranular pores in the spherical particle. The fast decomposition rate in a vacuum creates smaller crystallites, and the following higher calcination temperature results in the enhancement of pore elimination. The in-line transmittance of the transparent Y2O3 ceramics, vacuum sintered at 1750°C, was improved by increasing the particle density of the as-calcined powders. This result indicates that the high-density starting particles effectively enhance the pore elimination during the fabrication of transparent Y2O3 ceramics. [ABSTRACT FROM AUTHOR]

This study describes the synthesis of novel gene delivery vector with low toxicity and high transfection efficiency for magnetofection. The rational design of magnetofection vector called PPMag (PEI-associated polycaprolactone (PCL)-SPIONs) composed of oleic acid (OA) stabilized superparamagnetic iron oxide nanoparticles (SPPIONs) prepared by thermolysis of iron oleate with a combination of hydrophobic PCL and proton absorbing polymer polyethyleneimine (PEI) (PEI-PCL-SPIONs) is described. Encapsulation of amphiphilic PEI with SPIONs not only improves water dispersity of SPIONs, but also allows nucleic acid (NA) condensation and endosomal/lysosomal escape via proton sponge effect after internalization in cells. MTT cytotoxicity assay showed that cell viability was improved compared to conventional PEI-SPIONs. The luciferase activity of magneto-polyplexes treated cells significantly improved compared to both controls revealed that transfection efficiency of PPMag- pCIKlux polyplexes group was improved compared to naked pCIKlux group. The application underneath of a rare earth magnet significantly improve the transfection efficiency (i.e., the luciferase activity doubles) compared to cells without magnet, indicating that sedimentation induced by magnetic field plays important role in accumulation of magneto-polyplexes on cell surfaces. The results demonstrate that PPMag can be used as a novel gene transfection vector to improve transfection efficiency. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 145-154, 2017. [ABSTRACT FROM AUTHOR]

As highly integrated circuits are demanded for high-performance electric devices, small sizes of barium titanate (BaTiO3) as a dielectric material are desirable for the application of multilayer ceramic capacitors. Since the small sizes of the particles degrade the dielectric property, especially below a certain critical size, understanding the probable cause is significant for the high-performance capacitors. Here, we have demonstrated nanosized BaTiO3 with average size below 30 nm and a uniform size distribution. High-resolution transmission electron microscopy (TEM) shows that the as-synthesized BaTiO3 contains intragranular pores. We have analyzed the correlation between the intragranular pores inside nanoparticles and their phase ratio of cubic and tetragonal. We have found that the presence of the intragranular pores affects low tetragonality of BaTiO3 particles, and the intragranular pores are generated by the accumulation of hydroxyl groups during hydrothermal reaction. Formation and accumulation of intragranular pores have been investigated by ex-situ synchrotron X-ray diffraction and TEM analysis, suggesting the phase evolution model of nanosized BaTiO3. [ABSTRACT FROM AUTHOR]

A flexible piezoelectric energy harvester was demonstrated by an aerosol‐deposited PZT film to realize a self‐powered wireless sensor node system. The flexible harvesting device can generate a voltage of 200 V and a current of 35 μA. A self‐powered wireless sensor node was constructed by integrating the PZT harvester, a rectifying/storage circuit, and a wireless temperature‐sensor node to measure ambient temperature and wirelessly transmit the data to a monitor. [ABSTRACT FROM AUTHOR]

Dynamic wave interaction and crack propagation in glass have been observed with the edge-on impact ( EOI) style test method using an exploding bridged wire ( EBW) detonator. The existence of an interlayer or internal surface displayed meaningful wave distortions, delays, reflections, and decreasing amplitude. The interlayer materials used were rubber, stainless steel, and cut surface. The results indicate that the shocks passing the interlayer decrease following the impedance condition and that much of the crack is stopped at the interlayer. The damage pattern was analyzed with the energy and stress dissipation rate. [ABSTRACT FROM AUTHOR]

A unique hierarchical porous structure of silicon nitride ceramic with 76.5% porosity is fabricated by combining an ice-templating method and nitridation for a silicon powder. The porous silicon nitride ceramics were composed of a lamellar structure with aligned pore channels and ceramic walls filled with fibrous whiskers. This study is focused on the influences of freezing rate on the microstructures and properties of the silicon nitride ceramics. The properties were characterized by compressive strength and gas permeability, which were shown to vary with controlled microstructure. The compressive strength and the permeability reached up to 32.2 MPa and 0.035−12 m2, respectively. [ABSTRACT FROM AUTHOR]

Sodium layered oxides with mixed transition metals have received significant attention as positive electrode candidates for sodium-ion batteries because of their high reversible capacity. The phase transformations of layered compounds during electrochemical reactions are a pivotal feature for understanding the relationship between layered structures and electrochemical properties. A combination of in situ diffraction and ex situ X-ray absorption spectroscopy reveals the phase transition mechanism for the ternary transition metal system (Fe-Mn-Co) with P2 stacking. In situ synchrotron X-ray diffraction using a capillary-based microbattery cell shows a structural change from P2 to O2 in P2-Na0.7Fe0.4Mn0.4Co0.2O2 at the voltage plateau above 4.1 V on desodiation. The P2 structure is restored upon subsequent sodiation. The lattice parameter c in the O2 structure decreases significantly, resulting in a volumetric contraction of the lattice toward a fully charged state. Observations on the redox behavior of each transition metal in P2-Na0.7Fe0.4Mn0.4Co0.2O2 using X-ray absorption spectroscopy indicate that all transition metals are involved in the reduction/oxidation process. [ABSTRACT FROM AUTHOR]

Local fracture toughness gives us useful and important information to understand and improve mechanical properties of bulk ceramics. In this study, the local fracture toughness of silicon nitride (Si3N4) ceramics was directly measured using single-edge notched microcantilever beam specimens prepared by the focused ion beam technique. The measured fracture toughness of grain boundary of the Si3N4 ceramics is higher than the fracture toughness of SiAlON glass, which exists in the grain boundaries of Si3N4 ceramics. It is also shown that the fracture toughness of grain boundary depends on the rare earth oxide added as a sintering aid, which is expected in terms of the difference in the grain-boundary structure. The fracture toughness of a single β-Si3N4 grains is higher than the grain-boundary fracture toughness. It was also higher than the value estimated from ab initio calculations and surface energy, which means that any dissipative energy should be included in the fracture toughness of a grain in spite of the brittle fracture in Si3N4. The fracture toughness of polycrystals of Si3N4 ceramics measured using single-edge notched microcantilever beam specimens is intermediate between those of grains and grain boundaries, and it agrees with the estimated initial value of the Rcurve, KI0, in Si3N4 ceramics. [ABSTRACT FROM AUTHOR]

An aqueous sodium ion hybrid battery consisting of disodium naphthalenediimidesalt (anode) and KCo0.5Cu0.5Fe(CN)6 (cathode) is reported. Both electrode materials are inexpensive and exhibit appropriate operating voltages and robust reversibility under neutral aqueous electrolyte conditions, delivering a full‐cell voltage of 1.1 V with 88% capacity retention after 100 cycles. [ABSTRACT FROM AUTHOR]

The effects of sintering additives, microstructure, and morphology of second phase on the thermal conductivity of aluminum nitride ceramics are discussed in this review. The thermal conductivity of AlN is highly dependent on the types and amount of sintering additives, second phase morphology and microstructure. The morphology of second phase in AlN ceramics could be controlled by changing the cooling rate. The amount of second phase was able to be minimized by using the transient sintering additives. The thermal conductivity of AlN could be enhanced with the inclusion of the transient sintering additives. The thermal conductivity of AlN ceramics was evaluated by Raman spectroscopy. High temperature AC impedance studies were conducted to characterize the electrical conduction mechanism of AlN ceramics. [ABSTRACT FROM AUTHOR]

The electrical conductivity of CaF2-doped aluminum nitride ( AlN) ceramics was characterized at high temperatures, up to 500°C, by AC impedance spectroscopy. High thermal conductive CaF2-doped AlN ceramics were sintered with a second additive, Al2 O3, added to control the electrical conductivity. The effects of calcium fluoride ( CaF2) on microstructure and related electrical conductivity of AlN ceramics were examined. Investigation into the microstructure of specimens by TEM analysis showed that AlN ceramics sintered with only CaF2 additive have no secondary phases at grain boundaries. Addition of Al2 O3 caused the formation of amorphous phases at grain boundaries. Addition of Al2 O3 to CaF2-doped AlN ceramics at temperatures 200°C-500°C revealed a variation in electrical resistivity that was four orders of magnitude larger than for the specimen without Al2 O3. The amorphous phase at the grain boundary greatly increases the electrical resistivity of AlN ceramics without causing a significant deterioration of thermal conductivity. [ABSTRACT FROM AUTHOR]

The oxidation behaviors of ZrB2- 30 vol% SiC composites were investigated at 1500°C in air and under reducing conditions with oxygen partial pressures of 104 and 10 −8 Pa, respectively. The oxidation of ZrB2 and SiC were analyzed using transmission electron microscopy ( TEM). Due to kinetic difference of oxidation behavior, the three layers (surface silica-rich layer, oxide layer, and unreacted layer) were observed over a wide area of specimen in air, while the two layers (oxide layer, and unreacted layer) were observed over a narrow area in specimen under reducing condition. In oxide layer, the ZrB2 was oxidized to ZrO2 accompanied by division into small grains and the shape was also changed from faceted to round. This layer also consisted of amorphous SiO2 with residual SiC and found dispersed in TEM. Based on TEM analysis of ZrB2 - SiC composites tested under air and low oxygen partial pressure, the ZrB2 begins to oxidize preferentially and the SiC remained without any changes at the interface between oxidized layer and unreacted layer. [ABSTRACT FROM AUTHOR]

A facile synthetic strategy was implemented to obtain nanosized barium titanate ( BaTiO3) powders with tetragonal structure. The nanoparticles were synthesized using solvothermal process employing diethanolamine and triethanolamine to suppress the particle growth and the as-prepared nanopowders were characterized using X-ray diffraction, scanning electron microscopy, and high-resolution dispersive Raman spectroscopy. It was found that the particle size can be easily tuned by adjusting the experimental parameters while retaining the tetragonality. The average diameters of the particles prepared with and without the organic amines were found to be 80 and 100 nm, respectively. All the synthesized BaTiO3 nanopowders exhibit a narrow size distribution with a uniform morphology. Rietveld refinement of the XRD patterns and Raman spectra revealed that the synthesized BaTiO3 nanopowders have tetragonal asymmetry dominant structures. A slight decrease in the tetragonality of the prepared powders with decrease in particle size is attributed to the presence of cubic shell layer and inner defects. The tetragonal-dominant structure was also confirmed by normalizing the peak area of the Raman spectra. [ABSTRACT FROM AUTHOR]

The influence of ammonia on BaTiO3 particles prepared via hydrothermal synthesis is discussed. Two kinds of Ti-precursors, amorphous (with ammonia) and anatase (without ammonia), are synthesized by a hydrolysis reaction using Ti-butoxide as the starting material. Amorphous Ti-precursors are found to be excellent for this purpose and offer several advantages over anatase. Superior tetragonal properties of BaTiO3 powders with more uniform particle sizes can be achieved at 200°C after 24 h using amorphous Ti-precursors. X-ray photoelectron spectroscopy was carried out on both types of Ti-precursor, and a decrease in H2 O adsorption on the amorphous Ti-precursors is confirmed. It is considered that the reduction in H2 O adsorption on the Ti-precursors results from the shielding effects of ammonia and is attributed to a decreased formation of intragranular pores in the BaTiO3 particles. These suggested mechanisms are clarified by the results of in situ transmission electron microscopy observations and density measurements of the hydrothermally synthesized BaTiO3. [ABSTRACT FROM AUTHOR]

Abstract: Typical autosomal recessive juvenile Parkinsonism (AR-JP) is resulted from the loss of function mutation in the parkin gene. In an effort to learn more about the cell type-specific functional role of parkin, we used in vitro model such as locus coeruleus (LC) noradrenergic (NA) neuronal progenitor cell line, LC3541. Employing this in vitro model, we revealed that parkin plays a crucial role in phenotypic differentiation of NA neurons. Our results showed that parkin mRNA was expressed during the differentiation of NA neuronal progenitor cell line and that the level of the parkin mRNA was down-regulated by oxidative stress in the NA neuronal cells. Parkin protein overexpression in LC3541 cells induced expression of NA markers (TH, phox2a and DBH). Small interfering RNA (SiRNA) for parkin supressed NA differentiation and DBH expression. Preventing protein kinase A (PKA) activation with PKI attenuated expression of DBH in parkin overexpressed LC3541 cells. These findings suggest that the relative abundance of parkin enhances differentiation of NA phenotypes via a PKA-dependent pathway. [Copyright &y& Elsevier]

Abstract: Heat shock factor 1 (HSF1) is a major transactivator of heat shock genes in response to stress and mediates cell protection against various harmful conditions. In this study, we identified the interaction of CHIP (carboxyl terminus of the heat shock cognate protein 70-interacting protein) with the N-terminus of HSF1. Using GST full-down assay, we found that CHIP directly interacts with C-terminal deleted HSF1 (a.a. 1–290) but not with full-length HSF1 under non-stressed conditions. Interestingly, interaction of CHIP with full-length HSF1 was induced by heat shock treatment. The structural change of HSF1 was observed under heat stressed conditions by CD spectra. These observations demonstrate the direct interaction between HSF1 and CHIP and this interaction requires conformational change of HSF1 by heat stress. [Copyright &y& Elsevier]