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YFeO 3 is one of important magneto optic crystals with perovskite structure. The anisotropy of the crystal leads to different physical and chemical properties of the crystal in different directions. In this work, YFeO 3 crystals were grown by hydrothermal method and the effects of different mineralizers on the crystal growth were investigated. The results showed that the mineralizer could affect the growth direction of crystal plane during the hydrothermal crystallization process. YFeO 3 crystals with various morphologies were grown by adjusting the concentration of the mineralizer under hydrothermal conditions. The transformations between the crystal planes during crystallization were studied by modeling, and the stabilities of {002} and {110} crystal planes under the action of KOH and NaOH were determined. The effects of urea on YFeO 3 crystal planes and NH 4 + on {002}, {020} and small crystal planes were investigated. Furthermore, the exposure ratio of YFeO 3 crystal plane has great influence on its magnetization and coercive field. Finally, the formation and change mechanism of YFeO 3 crystals by the hydrothermal method were proposed, providing evidence for further study of the dependence of the shape of YFeO 3 on ferromagnetism. [ABSTRACT FROM AUTHOR]

Cu2+ doped SrZrO 3 (SrZr 1-x Cu x O 3 , x = 0, 0.01, 0.03, 0.05 and 0.07) perovskite powders were prepared by sol-gel method with Zr(NO 3) 4 ·5H 2 O, Sr(NO 3) 2 and Cu(NO 3) 2 ·2.5H 2 O as raw material. The influence of the ratio of metal ion to citric acid, pH value, and calcination temperature on the synthesis of high-purity SrZrO 3 powder and the infrared emissivity characteristics of the synthesized material was systematically studied. XRD, XPS, FT-IR and dual-band emittance measuring instrument were used to study the phase composition, microstructure of the sample and the effect of copper ion doping on the infrared emittance of SrZrO 3 at 3–5 μm. The results show that the infrared emissivity of SrZrO 3 doped with Cu2+ is lower than that of SrZrO 3. When x = 0.03, the infrared emissivity at room temperature of 3∼5 μm reaches the lowest value of 0.4259. With the increase of temperature and time, SrZr 1-x Cu x O 3 showed better thermal infrared properties, and the samples all showed weak thermal infrared intensity, and the surface temperature was lower than the background temperature and relatively stable. These findings suggest that Cu2+-doped SrZrO 3 holds great potential as a promising candidate material for infrared stealth applications. The novelties of this work are as follows: • High-temperature infrared stealth materials can be applied to high-temperature parts such as military aircraft engines, which plays a very important role in ensuring the safety of aircraft. SrZrO 3 and Cu2+ doped SrZrO 3 powder was prepared by sol-gel method. The influence of the metal ion to citric acid ratio, pH value, and calcination temperature on the synthesis of high-purity SrZrO 3 powder was systematically studied. Optimal conditions for the preparation of SrZrO 3 were obtained. • In order to obtain infrared stealth materials with higher stealth performance, we constructed a copper-ion doped strontium zirconate material system. A series of Cu2+ doped SrZrO 3 were fabricated and the phase composition, microstructure, grain size of the samples were investigated using XRD, SEM, XPS, FT-IR and nanometer particle size and Zeta potential analyzer. • The Infrared stealth characteristic of synthetic materials were investigated. It was observed that Cu2+ doped SrZrO 3 exhibited lower infrared emissivity compared to pure SrZrO 3. Notably, when x = 0.03, the infrared emissivity at room temperature within the range of 3∼5 μm reached its lowest value, measuring 0.4259. With the increase of temperature and time, SrZr 1-x Cu x O 3 showed better thermal infrared properties, and the samples all showed weak thermal infrared intensity, and the surface temperature was lower than the background temperature and relatively stable. The discussions we've had have laid the groundwork for future research on strontium zirconate. To date, there haven't been any reports of preparing copper ion-doped strontium zirconate (SrZr 1-x Cu x O 3) using the sol-gel method. We believe that SrZr 1-x Cu x O 3 holds great promise for infrared stealth applications, laying the groundwork for further research. [ABSTRACT FROM AUTHOR]

Developing highly efficient and stable non-precious metal electrocatalysts for the oxygen evolution reaction (OER) is an ongoing challenge due to the sluggish kinetics of the OER. In this study, the (Ni,Fe,V)3S4–NiS nanoheterostructure rich in Ni3+ was obtained by sulfidizing the NiFeV layered double hydroxide hydrogen precursor. The introduction of Fe and V effectively modified the electronic structure of NixSy and increased the content of Ni3+, which was conducive to enhancing the chemisorption of OH− and promoting the transfer of electrons to the surface during the OER process. At the same time, the self-supporting porous structure, the unique metallic characteristics of NixSy (continuous Ni–Ni bonds) and excellent electrical conductivity can facilitate electrolyte diffusion and bubble release. The designed (Ni,Fe,V)3S4–NiS/NF electrode shows excellent electrocatalytic OER performance with an overpotential of 236 mV at a current density of 10 mA cm−2, ultra-low Tafel slope (53.7 mV dec−1) and excellent long-term stability. Therefore, this work offers a simple strategy to design an efficient Ni based OER electrocatalyst enriched with Ni3+ sites by co-doping high-valence ions. [ABSTRACT FROM AUTHOR]

To facilitate functional investigation of the role of NADPH oxidase 1 (NOX1) and associated reactive oxygen species in cancer cell signaling, we report herein the development and characterization of a novel mouse monoclonal antibody that specifically recognizes the C-terminal region of the NOX1 protein. The antibody was validated in stable NOX1 overexpression and knockout systems, and demonstrates wide applicability for Western blot analysis, confocal microscopy, flow cytometry, and immunohistochemistry. We employed our NOX1 antibody to characterize NOX1 expression in a panel of 30 human colorectal cancer cell lines, and correlated protein expression with NOX1 mRNA expression and superoxide production in a subset of these cells. Although a significant correlation between oncogenic RAS status and NOX1 mRNA levels could not be demonstrated in colon cancer cell lines, RAS mutational status did correlate with NOX1 expression in human colon cancer surgical specimens. Immunohistochemical analysis of a comprehensive set of tissue microarrays comprising over 1,200 formalin-fixed, paraffin-embedded tissue cores from human epithelial tumors and inflammatory disease confirmed that NOX1 is overexpressed in human colon and small intestinal adenocarcinomas, as well as adenomatous polyps, compared to adjacent, uninvolved intestinal mucosae. In contradistinction to prior studies, we did not find evidence of NOX1 overexpression at the protein level in tumors versus histologically normal tissues in prostate, lung, ovarian, or breast carcinomas. This study constitutes the most comprehensive histopathological characterization of NOX1 to date in cellular models of colon cancer and in normal and malignant human tissues using a thoroughly evaluated monoclonal antibody. It also further establishes NOX1 as a clinically relevant therapeutic target in colorectal and small intestinal cancer. [ABSTRACT FROM AUTHOR]

The BiFeO3(BFO) and Bi0.95Nd0.05Fe1-xAlxO3 (x = 0, 0.03, 0.05, 0.075, 0.1) powders were prepared at 200 °C for 24 h by hydrothermal method. The effects of Al doping content on the structure, morphology, magnetic, and photocatalytic properties were studied. X-ray diffraction (XRD) and Fourier transform infrared spectrometer (FTIR) demonstrated the compounds are distorted rhombohedral perovskite structure without any other heterogeneity and structural transition. Field emission scanning electron microscope (FESEM) reflected surface of compounds is a dense, agglomerated sphere. As the concentration of Al3+ increases, a small part of the spherical crystallites eventually becomes cauliflower shape. Energy-dispersive X-ray (EDS) showed the Bi0.95Nd0.05Fe0.95Al0.05O3 sample mainly consists of five elements (Bi, Fe, O, Nd, Al) and atom radio matched well with the formula. Vibrating sample magnetometer (VSM) integrated in a physical property measurement system (PPMS-9) illustrated introducing Nd3+ ions into BFO will enhance its magnetism at room temperature. However, with the increase of non-magnetic ion Al3+ concentration in Bi0.95Nd0.05Fe1-xAlxO3 (x = 0, 0.03, 0.05, 0.075, 0.1), the network structure of Fe-O-Fe was destroyed, which led to the decrease of its net magnetization, so that the hysteresis loop shows paramagnetism. The photocatalytic performance of BFO increased initially and decreased afterwards as Al3+ concentration increased, and the best catalytic performance was achieved at x = 0.05. [ABSTRACT FROM AUTHOR]

Nd, Er co-doped YFeO3 compounds were synthesized by sol-gel method. The prepared compounds were characterized by powder x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive x-ray (EDX), and vibrating sample magnetometer (VSM) integrated in a physical property measurement system (PPMS-9), respectively. The results show that the compounds possess orthorhombic perovskite structure. The Y0.5Er0.1Nd0.4FeO3 compound mainly consists of five elements (Er, Nd, Y, Fe, and O) and atom ratio matched well with the formula. With the increase of Nd3+ doping content in Y0.5Er0.5−xNdxFeO3 (x = 0, 0.1, 0.2, 0.3, and 0.4), the coercivity increases gradually while the saturation magnetization and remanent magnetization decrease at the same time. Introducing Nd3+ and Er3+ ions into YFeO3 will make a change on a structure distortion, resulting in the decrease of the Fe-O-Fe angle and the consequent reduction of superexchange effect. From our research results, the relationship between the r (R3+) and the superexchange bond angle is different from pure-phase orthoferrites R FeO3. [ABSTRACT FROM AUTHOR]

Silicon carbide reticulated porous ceramics with a regular shape were successfully prepared by combining three-dimensional (3D) printing, gelcasting and liquid drying. A 3D reticulated structured polyvinyl alcohol (PVA) mould was first fabricated by 3D printing, and then a slurry with a high-loading of SiC was gelcast into it. The PVA mould could be removed without any damage to form the gelled SiC structure by immersion in an aqueous solution, i.e. by liquid drying. After sintering, dense SiC ceramics with reticulated structure were obtained. Zeta potentials, rheological properties, and gelling behaviors of the slurry were studied together with liquid drying technology and characteristics of the ceramics. The present method shows good potential for fabricating porous and/or complex-shaped high-quality ceramics, and could also be applied in various kinds of advanced ceramics. [ABSTRACT FROM AUTHOR]

A series of single phase Y 1− x Er x FeO 3 (0≤ x ≤1) orthoferrite samples were synthesized by sol-gel method and their magnetic properties were studied in detail. The prepared samples were characterized by X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and differential scanning calorimetry (DSC). The obviously weak ferromagnetic property, which caused by Dzialoshinski Moriya (DM) antisymmetric exchange mechanism, was observed in YFeO 3 for the magnetization jump at H=0 Oe. The magnetization of YFeO 3 was evidently changed by doping Er 3+ . The increase of the Er 3+ content in Y 1− x Er x FeO 3 greatly enhanced the paramagnetic component and gradually decreased the ferromagnetic component. [ABSTRACT FROM AUTHOR]

The prismy YFeO with (202)-preferred orientation was successfully synthesized through hydrothermal process at 240 C for 9 h with the ratio 1:1 of Y:Fe. The prepared YFeO powders were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), physical properties measurement system (PPMS), and differential scanning calorimetry (DSC), respectively. The results show the prepared YFeO has (202)-preferred orientation. The prismatic YFeO powders mainly consist of three elements (Y, Fe, and O), and atom ratio matched well with the formula. YFeO can simultaneously present obvious weak ferromagnetic and antiferromagnetic properties. In addition, the Néel temperature of YFeO is 349 C. [ABSTRACT FROM AUTHOR]

The defence ability of Fenneropenaeus chinensis and Marsupenaeus japonicus against the intrusion of the white spot syndrome virus (WSSV) was compared after injecting WSSV intramuscularly by recording cumulative mortality, diagnosing the virus and examining variations in immunological parameters including the total haemocyte counts (THCs), phagocytic percentage (PP), plasma protein concentration (PPC), phenoloxidase (PO) and nitric oxide synthase (NOS) activity. The results showed that the variations in the immunological parameters of F. chinensis and M. japonicus showed similar trends. The THCs of the two species decreased significantly postchallenge of WSSV. The virus was detected at 78 h in M. japonicus and at 42 h in F. chinensis after infection, which was in correlation with the accumulative mortality, and the variations in PO, PP, NOS and PPC in the two species. All shrimps of F. chinensis in the mortality experiment died within 66 h, much more quickly than M. japonicus, whose cumulative mortality reached 100% after 198 h. In conclusion, the immune system of M. japonicus has a stronger resistant ability to antagonize and endure the invasion of WSSV than that of F. chinensis. [ABSTRACT FROM AUTHOR]

Abstract: A 15vol% SiC whisker reinforced MoSi2 matrix composite has been successfully prepared by spark plasma sintering via in situ processing. After sintering, a uniform dispersion of SiC whiskers is obtained in the MoSi2 matrix based on the reaction between Mo powders, carbon and Si3N4 whiskers. XRD results show that the sintered products are composed of MoSi2, Mo4.8Si3C0.6 and SiC phases. Sintered composites exhibit higher than 89.9% of theoretical density. Vickers hardness and fracture toughness of the composites are in the range of 9.98–12.18GPa and 4.59–8.45MPam1/2, respectively. [Copyright &y& Elsevier]

Abstract: β-Si3N4 whiskers with diameter of 0.5–2μm and aspect ratio of 10–15 have been successfully prepared by combustion synthesis under 30–50atm nitrogen pressure. The addition of MgSiN2 powder plays a significant role in the growth of β-Si3N4 whiskers. The as-prepared products were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). [Copyright &y& Elsevier]

Abstract: The activation of self-propagating combustion reactions in the tungsten carbide–cobalt (WC-Co) system was achieved by using an electric field. Self-sustaining combustion in elemental reactants with composition corresponding to WC-x wt.% Co (0 ≤ x ≤ 10) composites can be activated only when the imposed field is above a threshold value. The nature of combustion products depended on the magnitude of the field. The relative strength of W2C diffraction peaks in XRD diagram decreased when moving from the reactants region to the final products one or increasing electric field on the reactants. The effect of the relative density of the reactant compacts on the synthesis of WC-Co composites was also investigated. Finally, the reaction mechanism of WC-Co composites was proposed. X-ray and microscopic analysis of the quenched combustion front suggests that the synthesis of WC is a process involving the solid diffusion of carbon into a carbide layer. Molten Co redounds the transformation from W2C to WC phase. [Copyright &y& Elsevier]

To study response to white spot syndrome virus (WSSV) under ammonia stress, Penaeus japonicus were exposed to 5 mg l−1 ammonia-N and challenged orally with WSSV (NW). Controls consisted of an ammonia-N-exposed control group (N), a WSSV-challenged positive control group (W), and an untreated control group (control). Immune parameters measured were total haemocyte count (THC), haemocyte phagocytosis, plasma protein content and haemolymph enzymatic activities for prophenoloxidase (proPO), alkaline phosphatase (ALP), and nitric oxide synthase (NOS). THC and plasma protein had downward trends with time in all treatment groups (NW, N, and W) in contrast to the untreated control group (control). The percentage phagocytosis, NOS activity, and ALP and proPO activity of W and NW decreased initially then increased from 6 to 78 h (except for NOS and ALP, from 6 to 54 h) before declining thereafter until the end of the experiment. Compared with untreated controls (control), there was a downward trend for all measured parameters in the treatment groups (N, NW, and W), but the degree was W>NW>N. WSSV was detected at 78 h postchallenge in both W and NW. In conclusion, 5 mg l−1 ammonia-N reduced the immunocompetence of P. japonicus and may have decreased the virulence of WSSV. [Copyright &y& Elsevier]

The field-activated, pressure-assisted combustion synthesis (FAPACS) process, which combines the simultaneous synthesis and densification of materials, was utilized to produce WC–10 wt.% Ni composites from reactant mixtures of W, Ni, and different carbon sources. The product composition, density, and microhardness of WC–Ni composites fabricated through the FAPACS process were investigated. The results show that the Vickers microhardness and toughness were 1287 kg/mm2 and 7.8 MPa m1/2 for the product made with activated carbon, and 1424 kg/mm2 and 5.9 MPa m1/2 with carbon black. [Copyright &y& Elsevier]

FAPACS process was utilized to produce WC–10wt%Co composites from reactants’ mixtures of tungsten, cobalt and different kinds of carbon sources (activated carbon and carbon black). The Vickers microhardness of end products were 1804 kg/mm2 for the former and 1899 kg/mm2 for the latter. [Copyright &y& Elsevier]

The field-activated pressure-assisted combustion synthesis (FAPACS) process, which combines the simultaneous synthesis and densification of materials, was utilized to produce tungsten carbides material from tungsten and carbon powders with different mole ratio between them, i.e. W+1.0C, W+1.1C, W+1.2C, W+1.3C and W+1.4C. The percentages of the total shrinkage occurring before and during the synthesis reaction were measured. The effects of the temperature, the reactants composition, different carbon sources on the products composition, densities and microhardness were investigated. The end-product relative densities ranged from 81.1 to 89.9%. Vickers microhardness measurements (at 1 kg force) on the dense samples gave values ranging from 731 to 423 kg mm−2. [Copyright &y& Elsevier]

The activation of self-propagating combustion reactions in the W–C system was achieved by using an electric field. Self-sustaining combustion in elemental reactants with the composition corresponding to WC can be activated only when the imposed field is above the threshold value of 1V cm−1. The nature of the combustion products depended on the magnitude of the field. The product consisted of two kinds of tungsten carbides, WC and W2C. The effects of tungsten particle sizes and the relative densities of the reactant compacts on the synthesis of tungsten carbide were also investigated. Finally, the reaction mechanism of tungsten carbide was proposed. X-ray and microscopic analysis of the quenched combustion front suggested that the synthesis of WC is a process involving the solid diffusion of carbon into a carbide layer. W2C is the intermediate phase between WC and reactants (W and C). [Copyright &y& Elsevier]

The field-activated pressure-assisted combustion synthesis (FAPACS) process, which combines the simultaneous synthesis and densification of materials, was utilized to produce WC–Co–Ni composites from reactant mixtures of W, C, Co and Ni. The effects of the reactant compositions on the compositions, densities and microhardness of synthesized products were investigated. The results show, relative densities of the fabricated products ranged from 97.7 to 99.3%. Vickers microhardness measurement (at 50 kg force) on the dense samples gave values ranging from 15.28 to 18.99 GPa. [Copyright &y& Elsevier]

The field-activated, and pressure-assisted combustion synthesis (FAPACS) process, which combines the simultaneous synthesis and densification of materials, was utilized to produce WC–Ni composites from powdered reactants, mixtures of tungsten, carbon and nickel. These reactants were subjected to high DC currents and uniaxial pressures. Under these conditions, a reaction is initiated by field activation and completed within a short period of time. Several experimental parameters, such as pulse current, power-controlled mode, temperature-increasing rate, maximum temperature and pressure during FAPACS on the relative densities of products were studied. Finally, the material with nearly complete density was fabricated. The percentage of the total shrinkage occurring before and during the synthesis reaction and addition densification was measured. The relative density of the end product and Vickers microhardness measurement (at 50 kg force) on the dense sample is 99.2% and 1424 kg mm−2, respectively. [Copyright &y& Elsevier]

The activation of self-propagating combustion reactions in the system of tungsten and carbon and its composites with cobalt as additive was achieved using an electric field. The reaction mechanism of Field-Activated Combustion Synthesis (FACS) of tungsten carbide and its composites has been investigated using the quenching sample method. By turning off the electric field during FACS, a series of combustion products with different phase compositions has been obtained. Layer to layer X-ray and microscopic analyses of these combustion products across the quenched combustion front suggest that the synthesis of WC involves the solid-phase diffusion of carbon into a carbide layer. W2C is the intermediate phase between WC and the reactants (W and C). A metallic additive produces liquid phase and accelerates the diffusion of the solid reactants (W and C); this facilitates the formation of W2C and the transformation of W2C to WC. Moreover, molten Co reacts with W and W2C to form mixed compounds of type WxCyCoz. [Copyright &y& Elsevier]

The activation of self-propagating combustion reactions in the WC–Ni system was investigated by using an electric field. Self-sustaining combustion in elemental reactants with composition corresponding to WC–x wt.%Ni (0⩽x⩽10) composites can be activated only when the imposed field is above a threshold value. The nature of combustion products depended on the magnitude of the field. The products contained the high temperature phase (WC), low temperature phase (W2C) and mixed compounds of type Ni2W4C. WC diffraction peaks in X-ray diffraction diagram shifted right when moving from the reactants region to the final product one or increasing electric field. The effect of the relative density of the reactants compact on the synthesis of WC–Ni was also investigated. Moreover, the reaction mechanism of WC–Ni is proposed. X-ray and microscopic analysis of the quenched combustion front suggests that the synthesis of WC is a process involving the solid diffusion of carbon into a carbide layer. Molten Ni reacts with W and W2C to form intermediate phase, which decomposes into WC and Ni. Molten Ni redounds the transformation from W2C to WC phase. [Copyright &y& Elsevier]

AlN-borosilicate glass composites were fabricated on the parabolic flight plane by using a self-propagating high-temperature synthesis (SHS) chemical oven. The effects of different gravity levels on the material transition and the microstructure of composites were investigated. The results show that AlN crystal and glass segregated in elevated gravity; on the contrary, the composites with uniform distribution of multiphases can be obtained in microgravity, which proves the microgravity environment is good condition to prepare improved AlN/glass composites. [Copyright &y& Elsevier]

Abstract: This paper deals with the formation of boron carbide (B4C) powders from Na2B4O7 +Mg+C system by self-propagating high-temperature synthesis (SHS) method. B4C without impurities could be obtained after the acid enrichment and distilled water washing. The reaction mechanism of SHS of B4C was proposed: the synthesis of B4C is a process involving the decomposition of Na2B4O7 into the intermediate phase B2O3, which reacts with Mg and carbon to form B4C. [Copyright &y& Elsevier]

Graphitic carbon nitride (g-C3N4), as a carbon support material with excellent stability and abundant active sites, has found widespread applications in various fields, including photocatalytic water splitting, electrolysis of water, and CO2 reduction. Presently, research on the modification of g-C3N4 primarily focuses on atomic doping, defect engineering, and the decoration of metal nanoparticles. In this study, a method involving the high-temperature pyrolysis of a solution containing thiourea and urea was successfully employed to synthesize sulfur-doped porous g-C3N4 (S-C3N4) nanosheets. Subsequently, PtCu nanoparticles were loaded onto the S-C3N4 through a hydrothermal process. In the case of Pt loading of less than half of 20% Pt/C, this catalyst exhibited a low overpotential of only 10 mV at a current density of 10 mA cm−2, which is significantly better than the 35 mV overpotential of 20% Pt/C. Furthermore, after a long period of continuous current stability testing, the overpotential of the catalyst did not increase by more than 30 mV, demonstrating excellent stability. The porous S-C3N4 nanosheets possess a large specific surface area, providing abundant active sites for the HER reaction. This research introduces a fresh method for creating innovative catalysts based on Pt alloys supported by a carbon carrier. [ABSTRACT FROM AUTHOR]

Pro-inflammatory cytokines upregulate the expression of the H 2 O 2 -producing NADPH oxidase dual oxidase 2 (DUOX2)2 which, when elevated, adversely affects survival from pancreatic ductal adenocarcinoma (PDAC). Because the cGAS-STING pathway is known to initiate pro-inflammatory cytokine expression following uptake of exogenous DNA, we examined whether activation of cGAS-STING could play a role in the generation of reactive oxygen species by PDAC cells. Here, we found that a variety of exogenous DNA species markedly increased the production of cGAMP, the phosphorylation of TBK1 and IRF3, and the translocation of phosphorylated IRF3 into the nucleus, leading to a significant, IRF3-dependent enhancement of DUOX2 expression, and a significant flux of H 2 O 2 in PDAC cells. However, unlike the canonical cGAS-STING pathway, DNA-related DUOX2 upregulation was not mediated by NF-κB. Although exogenous IFN-β significantly increased Stat1/2-associated DUOX2 expression, intracellular IFN-β signaling that followed cGAMP or DNA exposure did not itself increase DUOX2 levels. Finally, DUOX2 upregulation subsequent to cGAS-STING activation was accompanied by the enhanced, normoxic expression of HIF-1α and VEGF-A as well as DNA double strand cleavage, suggesting that cGAS-STING signaling may support the development of an oxidative, pro-angiogenic microenvironment that could contribute to the inflammation-related genetic instability of pancreatic cancer. [Display omitted] • Introduction of exogenous DNA by pancreatic cancer cells enhances the expression of DUOX2. • DNA-induced DUOX2 activity results from activation of the cGAS-STING pathway. • CGAS-STING-related DUOX2 expression leads to H 2 O 2 -related DNA double strand scission. [ABSTRACT FROM AUTHOR]

Ultrathin porous Co3O4 nanosheets are synthesized successfully, the thickness of which is about three unit-cell dimensions. The enhanced oxygen evolution reaction (OER) performance and electronic interaction between Co3O4 and Au is firstly reported in Co3O4 ultrathin porous nanosheets by physically mixing with Au nanoparticles. With the loading of the Au nanoparticles, the current density of ultrathin porous Co3O4 nanosheets is enhanced from 9.97 to 14.76 mA cm−2 at an overpotential of 0.5 V, and the overpotential required for 10 mA cm−2 decreases from 0.51 to 0.46 V, smaller than that of commercial IrO2 (0.54 V). Furthermore, a smaller Tafel slope and excellent durability are also obtained. Raman spectra, XPS measurement, and X-ray absorption near edge structure spectra (XANES) show that the enhanced OER ascribed to a higher Co2+/Co3+ ratio and quicker charge transfer due to the electronic interaction between Au and ultrathin Co3O4 nanosheets with low-coordinated surface, and Co2+ ions are beneficial for the formation of CoOOH active sites. [ABSTRACT FROM AUTHOR]

Abstract: SiC whisker reinforced MoSi2 composite powder has been successfully synthesized by “chemical oven” combustion synthesis method. The mixtures of Si and Ti were ignited as chemical oven. XRD result shows that the combustion product is mainly composed of MoSi2 and SiC phases. SEM photo and EDS result show that SiC whisker is formed during this process. [Copyright &y& Elsevier]

The NADPH oxidases (NOXs) play a recognized role in the development and progression of inflammation-associated disorders, as well as cancer. To date, several NOX inhibitors have been developed, through either high throughput screening or targeted disruption of NOX interaction partners, although only a few have reached clinical trials. To improve the efficacy and bioavailability of the iodonium class NOX inhibitor diphenylene iodonium (DPI), we synthesized 36 analogs of DPI, focusing on improved solubility and functionalization. The inhibitory activity of the analogs was interrogated through cell viability and clonogenic studies with a colon cancer cell line (HT-29) that depends on NOX for its proliferative potential. Lack of altered cellular respiration at relevant iodonium analog concentrations was also demonstrated. Additionally, inhibition of ROS generation was evaluated with a luminescence assay for superoxide, or by Amplex Red® assay for H 2 O 2 production, in cell models expressing specific NOX isoforms. DPI and four analogs (NSCs 740104, 751140, 734428, 737392) strongly inhibited HT-29 cell growth and ROS production with nanomolar potency in a concentration-dependent manner. NSC 737392 and 734428, which both feature nitro functional groups at the meta position, had >10-fold higher activity against ROS production by cells that overexpress dual oxidase 2 (DUOX2) than the other compounds examined (IC 50 ≈ 200–400 nM). Based on these results, we synthesized and tested NSC 780521 with optimized potency against DUOX2. Iodonium analogs with anticancer activity, including the first generation of targeted agents with improved specificity against DUOX2, may provide a novel therapeutic approach to NOX-driven tumors. [ABSTRACT FROM AUTHOR]

In this paper, ZnO/Ti 3 C 2 T x composites containing different proportions of Ti 3 C 2 T x were synthesized by hydrothermal method. The effects of different proportions of MXene content on the gas sensing properties of ZnO/Ti 3 C 2 T x composites were studied. It is found that ZnO/Ti 3 C 2 T x composites show a good response to acetone and excellent reversibility and the ZnO/Ti 3 C 2 T x composites containing 2 wt% Ti 3 C 2 T x had the highest response to acetone. The gas-sensing performance of ZnO/multi-layer MXene and ZnO/few-layer MXene were compared. The results showed that ZnO/Ti 3 C 2 T x composites with few-layer MXene had a higher response to acetone, 14.4, indicating that the few-layer MXene solution has better dispersion for ZnO and gas-sensing properties. Finally, the gas sensing mechanism of few-layer MXene/ZnO was suggest. [Display omitted] • ZnO/Ti 3 C 2 T x material was prepared by controllable hydrothermal method, and ZnO was uniformly dispersed on MXene. • ZnO/Ti 3 C 2 T x composites with few-layer MXene had a higher response to acetone owing to its better dispersion and synergistic effect. • The gas sensing mechanism of few-layer MXene/ZnO was suggest. [ABSTRACT FROM AUTHOR]

Abstract: Fine-grained Nd3+:Lu2O3 transparent ceramic was developed by a two-step sintering method in flowing H2 atmosphere at T 1 =1720°C for 15min and T 2 =1620°C for 10h. The initial nanopowders were synthesized by a wet chemical processing with a uniform particle size of about 40nm. The average grain size of the obtained 3at.% Nd3+:Lu2O3 ceramic was 406nm, which is ∼150 times smaller than the coarse-grained ceramic by normal H2 sintering. The emission intensity of the fine-grained transparent ceramic is 3 times of its coarse-grained counterpart, indicating higher Nd concentration without serious quenching in fine-grained transparent ceramic is possible, which agreed well with the prediction of an atomistic modeling work with YAG. EXAFS research demonstrated that with decreasing grain size, higher degree of disorder factor of the local environment of doped Nd atoms was discovered. [Copyright &y& Elsevier]

Significance: Reactive oxygen species (ROS) promote genomic instability, altered signal transduction, and an environment that can sustain tumor formation and growth. The NOX family of NADPH oxidases, membrane-bound epithelial superoxide and hydrogen peroxide producers, plays a critical role in the maintenance of immune function, cell growth, and apoptosis. The impact of NOX enzymes in carcinogenesis is currently being defined and may directly link chronic inflammation and NOX ROS-mediated tumor formation. Recent Advances: Increased interest in the function of NOX enzymes in tumor biology has spurred a surge of investigative effort to understand the variability of NOX expression levels in tumors and the effect of NOX activity on tumor cell proliferation. These initial efforts have demonstrated a wide variance in NOX distribution and expression levels across numerous cancers as well as in common tumor cell lines, suggesting that much remains to be discovered about the unique role of NOX-related ROS production within each system. Progression from in vitro cell line studies toward in vivo tumor tissue screening and xenograft models has begun to provide evidence supporting the importance of NOX expression in carcinogenesis. Critical Issues: A lack of universally available, isoform-specific antibodies and animal tumor models of inducible knockout or over-expression of NOX isoforms has hindered progress toward the completion of in vivo studies. Future Directions: In vivo validation experiments and the use of large, existing gene expression data sets should help define the best model systems for studying the NOX homologues in the context of cancer. Antioxid. Redox Signal. 20, 2873-2889. [ABSTRACT FROM AUTHOR]

Pancreatitis is associated with release of proinflammatory cytokines and reactive oxygen species and plays an important role in the development of pancreatic cancer. We recently demonstrated that dual oxidase (Duox)2, an NADPH oxidase essential for reactive oxygen species-related, gastrointestinal host defense, is regulated by IFN-γ-mediated Statl binding to the Duox2 promoter in pancreatic tumor lines. Because LPS enhances the development and invasiveness of pancreatic cancer in vivo following TLR4-related activation of NF-κB, we examined whether LPS, alone or combined with IFN-γ, regulated Duox2. We found that upregulation of TLR4 by IFN-γ in BxPC-3 and CFPAC-1 pancreatic cancer cells was augmented by LPS, resulting in activation of NF-κB, accumulation of NF-κB (p65) in the nucleus, and increased binding of p65 to the Duox2 promoter. TLR4 silencing with small interfering RNAs, as well as two independent NF-κB inhibitors, attenuated LPS- and IFN-γ-mediated Duox2 upregulation in BxPC-3 cells. Induction of Duox2 expression by IFN-γ and LPS may result from IFN-γ-related activation of Statl acting in concert with NF-κB-related upregulation of Duox2. Sustained extracellular accumulation of H2O2 generated by exposure to both LPS and IFN-γ was responsible for an ~50% decrease in BxPC-3 cell proliferation associated with a G1, cell cycle block, apoptosis, and DNA damage. We also demonstrated upregulation of Duox expression in vivo in pancreatic cancer xenografts and in patients with chronic pancreatitis. These results suggest that inflammatory cytokines can interact to produce a Duox-dependent pro-oxidant milieu that could increase the pathologic potential of pancreatic inflammation and pancreatic cancer cells. [ABSTRACT FROM AUTHOR]

Abstract: Flavoprotein-dependent reactive oxygen species (ROS) play a critical role in cytokine-mediated signal transduction in normal tissues and tumor cells. The flavoenzyme inhibitors diphenylene iodonium (DPI) and di-2-thienyliodonium (DTI) have been used to inhibit membrane-bound, flavoprotein-containing NADPH oxidases, including epithelial and leukocyte NADPH oxidases (Nox1-5 and Duox 1 and 2). Recent evidence suggests that DPI can decrease tumor cell proliferation; however, the molecular mechanisms involved remain poorly defined. To explore the mechanisms underlying DPI- and DTI-related tumor cell growth delay, we examined growth inhibition patterns produced by both agents in the NCI-60 tumor panel, and determined expression levels of Nox gene family members across these cell lines. Possible molecular targets were predicted using the COMPARE program. DPI was more potent than DTI (GI50: 10nM versus 10μM); DPI and DTI exposure produced unique patterns of growth inhibition when evaluated against the small molecule anticancer database of the National Cancer Institute. Growth inhibition profiling of DPI revealed a modest positive correlation with Nox1 levels; novel mechanisms of DPI and DTI action, including alterations in Stat, Erk1/2, and Akt pathways, were inferred by correlation with NCI-60 Affymetrix® array data. Exposure of HT-29 colon cancer cells, which express Nox1, to DPI and DTI confirmed their inhibitory effects on steady state ROS levels, and demonstrated decreased Stat, Erk1/2, and Akt signaling mediated by IL-4, IL-6, IL-13, and IL-22, possibly due to a concomitant increase in tumor cell phosphatase activity. These findings suggest that DPI and DTI may act therapeutically by altering ROS-related signal transduction. [Copyright &y& Elsevier]

Abstract: High purity Mn doped YFeO3 nanocrystals were readily prepared by sol–gel combustion method, with citric acid as the fuel. The doping effect on the structure and magnetic properties was systematically studied. X-ray diffraction and TEM results indicate that the samples are well crystallized. Orthorhombic YFeO3 crystallites can be obtained when calcined at 800°C. In YFe1−x Mn x O3 system for x ≤0.2, hexagonal structure exists as metastable phase and the calcined temperature has to be elevated to obtain pure orthorhombic phase. Distortion of the crystal structure was also observed, with changes in lattice parameters. The antiferromagnetic coupling was effectively strengthened with increased Mn content. This is possibly originated from the structural distortion which gives rise to enhanced antiferromagnetic superexchange interaction between Fe3+–Fe3+ and Fe3+–Mn3+. [Copyright &y& Elsevier]

Abstract: To understand the defense mechanisms of Crustacean animals, brine shrimp Artemia sinica prophenoloxidase (AsproPO) cDNA was cloned and its expression at early developmental stages was examined by reverse-transcription PCR (RT-PCR) and semi-quantitative RT-PCR, and activity of phenoloxidase (PO) at different developmental stages was further detected by using l-3,4-dihydroxyphenylalanine (l-DOPA) as a specific substrate in this study. It was found that the full-length of AsproPO cDNA is 2125 bp and it contains an open reading frame of 2100 bp encoding a protein of 699 amino acids. The deduced amino acid sequence of AsproPO has two putative copper binding sites highly conserved in Arthropods. Semi-quantitative RT-PCR analyses showed that the gene of AsproPO expressed at Emergence, Instar I and Instar II stages but did not at 0 h and 6 h stages. Activity measurement showed that PO activity could only be detected at Instar II stage but the other measured stages. All these implied that Artemia proPO immune system was complexly modulated during early development. [Copyright &y& Elsevier]

Abstract: To determine effective activators of crab hemocyanin (Hc) and the properties of Hc-derived phenoloxidase (HdPO), Hc, for the first time, was purified from hemolymph of Charybdis japonica, and the properties of activated HdPO were studied by using L-DOPA as a substrate. Three distinct subunits were isolated, and each had a molecular mass of about 80, 75 and 70 kDa, respectively. SDS and HLS were much effective in conversion of Hc into HdPO whose PO activity was optimal at pH 7.0 and temperature of 40 °C. The Km value of the HdPO was 2.90 mM for L-DOPA and 7.33 mM for tyrosine. The PO activity of HdPO was most sensitive to 1-phenyl-2-thiourea, cysteine and ascorbic acid, and much sensitive to thio urea and sodium sulfite. Based on its inhibition characteristics and the substrate specificity, this HdPO could be classified as a kind of tyrosinase-type phenoloxidase. The PO activity of HdPO was also strongly inhibited by Cu2+, Zn2+, ethylenediaminetetraacetic acid (EDTA) and diethyldithiocarbamate (DETC). The results with EDTA, DETC, and some metal ions, combined with the perfect recovery effect of Cu2+ on DETC-inhibited PO activity, indicate that the HdPO is a kind of copper-containing metalloenzyme. All these imply that the Hc, as an oxygen carrier, can be activated to have PO activities by SDS or HLS, and the activated HdPO has the properties of a tyrosinase-type copper-containing phenoloxidase. This study makes us to understand more easily the multifunctions of crustacean Hc in oxygen carrier and melaninization at certain stresses in host defence as well. [Copyright &y& Elsevier]

Abstract: TiN/Y-(α/β)-sialon ceramics with good mechanical properties were successfully obtained by pressureless sintering from SHS powder. XRD results showed the main phases of SHS powder to be α-sialon (68.5wt.%) and β-sialon (29.3wt.%). The microhardness, flexural strength and fracture toughness of the pressureless densified sialon ceramic reached 14.22GPa, 651MPa and 5.09MPam1/2, respectively. [Copyright &y& Elsevier]

The present work indicates through thermodynamic considerations that the calcium, barium-borosilicate glass, which was selected as the bonding agent in copper paste, is chemically compatible to aluminum nitride (AlN) substrate. Meanwhile it implicates the scarce of reactivity which results in poor adhesion strength between the copper thick film and the AlN substrate. However after pre-oxidized treatment on AlN substrate, the adhesion strength was improved significantly by about 1 kg/mm2 (at 20 vol.% glass frit) than that of the untreated AlN substrate, due to the improved reactivity of the glass frit. The adhesion strength is also demonstrated being affected by frit content and firing temperature. The optimum value (1.85 kg/mm2) was obtained when the copper paste (containing 20 vol.% glass frit) was printed on the pre-oxidized AlN substrate and subsequently fired at 850 °C. [Copyright &y& Elsevier]