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Searching for efficient, stable and low-cost nonprecious catalysts for oxygen and hydrogen evolution reactions (OER and HER) is highly desired in overall water splitting (OWS). Herein, presented is a nickel foam (NF)-supported MoS 2 /NiFeS 2 heterostructure, as an efficient electrocatalyst for OER, HER and OWS. The MoS 2 /NiFeS 2 /NF catalyst achieves a 500 mA cm−2 current density at a small overpotential of 303 mV for OER, and 228 mV for HER. Assembled as an electrolyzer for OWS, such a MoS 2 /NiFeS 2 /NF heterostructure catalyst shows a quite low cell voltage (≈1.79 V) at 500 mA cm−2, which is among the best values of current non-noble metal electrocatalysts. Even at the extremely large current density of 1000 mA cm−2, the MoS 2 /NiFeS 2 /NF catalyst presents low overpotentials of 314 and 253 mV for OER and HER, respectively. Furthermore, MoS 2 /NiFeS 2 /NF shows a ceaseless durability over 25 h with almost no change in the cell voltage. The superior catalytic activity and stability at large current densities (>500 mA cm−2) far exceed the benchmark RuO 2 and Pt/C catalysts. This work sheds a new light on the development of highly active and stable nonprecious electrocatalysts for industrial water electrolysis. [Display omitted] • MoS 2 /NiFeS 2 /NF shows ultrahigh activity for OER and HER at large current density. • Ultralow overpotentials (η 1000, OER = 314 mV, η 1000, HER = 254 mV) are needed. • MoS 2 /NiFeS 2 /NF exhibits ultralow cell voltage of 1.79 V@500 mA/cm2 for OWS. • The catalyst shows high stability with no decay in the CP test for OWS over 25 h. [ABSTRACT FROM AUTHOR]

Highlights • A genetic linkage map of Salvia miltiorrhiza was constructed based on genomic simple sequence repeat markers. • The genetic map with eight linkage groups spanned 397.5 cM with an average marker interval of 3.6 cM. • A total of six QTL were identified for salvianolic acid B, rosmarinic acid and lithospermic acid content, respectively. • These QTL will be useful for breeding to improve Salvia miltiorrhiza traits. Abstract Phenolic acids are one of the main active components in Salvia miltiorrhiza root, which have been proved to have extensive pharmacological activities. In this study, quantitative trait loci (QTL) for phenolic acids contents were identified by a new genetic map constructed based on genomic simple sequence repeat (SSR) markers. The results demonstrated that the map comprised eight linkage groups which were in accord with the haploid chromosome number of S. miltiorrhiza (2n = 2x = 16). The map spanned 397.5 cM with average inter-marker distance as 3.6 cM. A total of six QTL were identified through interval mapping, including three salvianolic acid B (SAB) content-related QTL on linkage group (LG) 7, two lithospermic acid (LA) content markers on LG2 and LG4, as well as one rosmarinic acid (RA) content-linked QTL on LG7. These QTL could be used in marker-assisted breeding for the phenolic acids contents of S. miltiorrhiza. [ABSTRACT FROM AUTHOR]

Abstract Three MnO 2 samples with different well-defined morphologies including nanoplates, nanorods and corallines are prepared through a simple chemical precipitation method and used as the promoter/support for Pt electrocatalysts (denoted as Pt/MnO 2 P , Pt/MnO 2 - R and Pt/MnO 2 C , respectively). The morphology effects of MnO 2 to the catalytic properties of Pt for methanol oxidation reaction (MOR) are intensively investigated. Results show that the catalytic properties of Pt are strongly dependent on the morphology of the promoter. Pt/MnO 2 - R with MnO 2 nanorods as the promoter shows the highest catalytic properties among the MnO 2 -promoted catalysts. The mass-specific activity and intrinsic activity of Pt in Pt/MnO 2 - R catalyst is 0.51 A mg−1 Pt and 11.54 A m−2 Pt , which is ca. 1.89 and 2.18 times that of commercial Pt/C catalysts (0.27 A mg−1 Pt and 5.29 A m−2 Pt), respectively. Change in the electronic structure of Pt is responsible for the enhancement in the catalytic properties of Pt/MnO 2 - R. Highlights • MnO 2 nanoplates, nanorods and corallines are used as the promoters to Pt for MOR. • Morphology effects of MnO 2 on the catalytic properties of Pt are investigated. • Pt/MnO 2 with MnO 2 nanorods as the promoter shows much higher catalytic properties. • Change in the electronic structure of Pt contributes to its enhanced activities. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (RGO) supported Pt m Au electrocatalysts with different atomic Pt/Au ratios ( m = 0.5–2.0) are prepared via co-reduction of H 2 PtCl 6 and HAuCl 4 . The catalysts are comprehensively characterized through TEM, XRD and XPS. The catalytic behaviors of the Pt m Au catalysts toward methanol oxidation reaction (MOR) in alkaline electrolyte are investigated via cyclic voltammetry (CV) and chronoamperometry (CA) techniques. Results show that methanol oxidation currents on the Pt m Au catalysts are higher than that on pure Pt catalyst, suggesting that the introduction of Au in Pt catalyst can significantly promote the catalytic properties of Pt. Among the Pt m Au catalysts, Pt 1.0 Au/RGO shows the highest mass-specific activity (MSA) and intrinsic activity (IA). The MSA and IA of Pt 1.0 Au/RGO is 0.72 A mg −1 Pt+Au and 105.4 A m −2 Pt , which are ca . 2.40 and 3.56 times those of Pt/RGO (0.30 A mg −1 Pt+Au and 29.6 A m −2 Pt ), respectively. CO stripping voltammograms and CV curves suggest that the improved electrocatalytic properties of the Pt m Au/RGO catalysts are especially attributed to the decreased CO formation rather than the facile removal of CO on the surface of Pt. The findings of this work have potential applications in understanding the mechanism of MOR and designing highly effective Pt-based anodic catalysts of direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Abstract: Composite metal oxides InxSnO2 are prepared with a simple hydrothermal process and used as functionalized support of Pt catalyst toward methanol electrooxidation reaction (MOR). The catalytic activity of Pt is strongly dependent on the composition of the support. Introduction of a small amount of In into SnO2 support exhibits much higher promoting effect to the Pt catalytic properties as compared with Pt/SnO2 and commercial Pt/C catalysts. The mass-specific activity (MSA) and intrinsic activity (IA) of Pt in Pt/In0.1SnO2 is 3.0 and 4.3 times that of Pt/C, respectively. Changes in Pt electronic structure arising from the interaction between Pt and the support are responsible for this improvement. Our findings clearly suggest that the composite metal oxides InxSnO2 can not only act as the catalyst support but also act as an effective promoter to Pt toward MOR, which would be promising in designing new catalysts that can replace the traditional catalytic nanostructure. [Copyright &y& Elsevier]

Abstract: Bimetallic Pd m Ag alloy nanostructures (m being the atomic Pd/Ag ratio, m = 0.1–1.5), prepared through a simple co-reduction process, are employed as the catalysts toward ethanol electro-oxidation reaction (EOR). XPS results show that the electronic structure of Pd can be modified due to the presence of Ag, which is crucial for the enhancement of the catalytic performance of the Pd m Ag/C catalysts. It is found that the catalytic activity of Pd was strongly dependent on the composition of the Pd m Ag/C catalysts, with the best performance found with the Pd0.5Ag/C. The mass-specific activity (MSA) and intrinsic activity (IA) data of Pd0.5Ag/C is 3.6 and 2.4 times higher than that of the monometallic Pd/C catalyst, respectively, which might be ascribed to the electronic and synergistic effect. These findings would be promising in understanding the mechanism of EOR on Pd-based catalysts and designing the bimetallic catalysts for direct ethanol fuel cells and other applications. [Copyright &y& Elsevier]

• Cu-doped RuO 2 catalyst is synthesized via calcination of amorphous RuCu sample. • The catalytic activities of Cu-RuO 2 for OER depend on the calcination temperature. • Cu-RuO 2 -300 shows an extremely low OER overpotential of 189 mV at 10 mA cm−2. • The activity is much higher than most OER catalysts reported in literature. • Large surface area and high-index facets are responsible for the high activity. The development of highly active and acid-stable catalysts for oxygen evolution reaction (OER) is necessary and challenging. In this work, we report a highly efficient Cu-doped RuO 2 OER electrocatalyst (Cu-RuO 2) synthesized via one-step calcination of amorphous RuCu sample in air atmosphere. Results show that the catalytic performances of Cu-RuO 2 catalysts toward OER are strongly dependent on the calcination temperature. Among the series of Cu-RuO 2 catalysts, Cu-RuO 2 prepared at the calcination temperature of 300 °C (Cu-RuO 2 -300) exhibits the highest activity for OER. At the current density of 10 mA cm−2, Cu-RuO 2 -300 shows an extremely low OER overpotential of 201 mV, which is much lower than the benchmark commercial RuO 2 (233 mV) and most noble metal/non-noble metal catalysts reported in literature. The Tafel slope is as low as 55 mV dec−1, which is also lower than that on RuO 2 catalyst (76 mV dec−1), suggesting a faster OER kinetics. In addition, Cu-RuO 2 -300 can maintain excellent durability in H 2 SO 4 electrolyte. During the chronopotentiometric (CP) test, the potential of Cu-RuO 2 -300 catalyst shows very small attenuation (65 mV) at the time of 24 h whereas that of the reference RuO 2 catalyst exhibits a 127 mV of change only within 4 h of test. Large electrochemical surface area and abundant exposed high-index facets are responsible for the high catalytic performances of the Cu-RuO 2 -300 catalyst. This work is instructive for the design and preparation of highly efficient and stable noble metal-based OER catalysts in acidic media. [ABSTRACT FROM AUTHOR]

Background & Aims: Dysregulation of Wnt signaling has been involved in gastric tumorigenesis by mechanisms that are not fully understood. The receptor for activated protein kinase C (RACK1, GNB2L1) is involved in development of different tumor types, but its expression and function have not been investigated in gastric tumors. Methods: We analyzed expression of RACK1 in gastric tumor samples and their matched normal tissues from 116 patients using immunohistochemistry. Effects of knockdown with small interfering RNAs or overexpression of RACK1 in gastric cancer cell lines were evaluated in cell growth and tumor xenograft. RACK1 signaling pathways were investigated in cells and zebrafish embryos using immunoblot, immunoprecipitation, microinjection, and in situ hybridization assays. Results: Expression of RACK1 was reduced in gastric tumor samples and correlated with depth of tumor infiltration and poor differentiation. Knockdown of RACK1 in gastric cancer cells accelerated their anchorage-independent proliferation in soft agar, whereas overexpression of RACK1 reduced their tumorigenicity in nude mice. RACK1 formed a complex with glycogen synthase kinase Gsk3β and Axin to promote the interaction between Gsk3β and β-catenin and thereby stabilized the β-catenin destruction complex. On stimulation of Wnt3a, RACK1 repressed Wnt signaling by inhibiting recruitment of Axin by Dishevelled 2 (Dvl2). Moreover, there was an inverse correlation between expression of RACK1 and localization of β-catenin to the cytoplasm/nucleus in human gastric tumor samples. Conclusions: RACK1 negatively regulates Wnt signaling pathway by stabilizing the β-catenin destruction complex and act as a tumor suppressor in gastric cancer cells. [Copyright &y& Elsevier]

Water electrolysis is an efficient approach for high-purity hydrogen production. However, the anodic sluggish oxygen evolution reaction (OER) always needs high overpotential and thus brings about superfluous electricity cost of water electrolysis. Therefore, exploiting highly efficient OER electrocatalysts with small overpotential especially at high current density will undoubtedly boost the development of industrial water electrolysis. Herein, we used a simple hydrothermal method to prepare a novel FeOOH–CoS nanocomposite on nickel foam (NF). The as-prepared FeOOH–CoS/NF catalyst displays an excellent OER performance with extremely low overpotentials of 306 and 329 mV at 500 and 1000 mA cm−2 in 1.0 M KOH, respectively. In addition, the FeOOH–CoS/NF catalyst can maintain excellent catalytic stability for more than 50 h, and the OER catalytic activity shows almost no attenuation no matter after 1000 repeated CV cycles or 50 h of stability test. The high catalytic activity and stability have exceeded most non-noble metal electrocatalysts reported in literature, which makes the FeOOH–CoS/NF composite catalyst have promising applications in the industrial water electrolysis. • Nickel foam (NF) supported FeOOH–CoS composite electrocatalyst is synthesized. • FeOOH–CoS/NF shows extremely low overpotential of OER at high current density. • FeOOH–CoS/NF can maintain excellent catalytic stability for more than 50 h. • Our work provides new insights in preparing non-noble metal OER catalysts. [ABSTRACT FROM AUTHOR]

The development of non-precious metal catalysts for the electrochemical oxygen evolution reaction (OER) is especially important for the water electrolysis process. Herein, a two-dimensional (2D) ultrathin hybrid Co–NiFe layered double hydroxide (LDH) is synthesized via a facile hydrothermal method. In 1.0 M KOH electrolyte, Co–NiFe LDH exhibits remarkable activities for OER. At the current density of 10 mA cm−2, it only needs an overpotential of 278 mV, which is ca. 50 mV and 20 mV lower than those for NiFe LDH (328 mV) and RuO 2 catalysts (298 mV), respectively. In addition, Co–NiFe LDH also shows impressive long-term stability for OER. Besides the stable morphology and crystal structure, the potential is always kept at 1.50 V and shows almost no attenuation during the 20 h of durability test. Changes in the electronic structure of LDH due to introduction of Co ions, as well as the large specific surface area facilitate the mass/electron transfer and the oxygen bubbles release, and thus lead to the enhanced catalytic properties for OER. This work can be informative not only for understanding the role of physical and electronic structures on OER but also for designing high-performance non-precious metal OER electrocatalysts. Two-dimensional (2D) ultrathin Co–NiFe LDH nanosheets show remarkable catalytic activity and long-term stability for the electrochemical evolution of oxygen. Image 1 • Co–NiFe layered double hydroxide is prepared via a facile hydrothermal method. • The doping of Co ions in NiFe LDH decreases the overpotential of OER by ca. 50 mV. • The potential of Co–NiFe LDH keeps constant during 20 h of stability test. • Large surface area and modified electronic structure contribute to the activity. [ABSTRACT FROM AUTHOR]

The promoting effect of metal oxides to Pt catalysts toward methanol oxidation reaction (MOR) has attracted widespread attention in recent years. In this communication, we report the promoting effect of MoO 3 to Pt catalyst by rationally designing and tuning the nanostructure of the catalysts. MoO 3 nanorods are firstly synthesized through hydrothermal method and used as the substrate for the deposition of polyaniline (PANI) layer. The PANI-MoO 3 composite nanostructures are then used as the support for Pt catalyst. Depending on the preparation method of Pt nanoparticles, the nanostructure can be PANI nanotube supported Pt (Pt/PANI) through etching MoO 3 nanorods with NaBH 4 and PANI-MoO 3 composite nanorods supported Pt (Pt/PANI-MoO 3 ). The catalytic properties of the two catalysts toward MOR are investigated. Results show that the current of methanol oxidation on Pt/PANI-MoO 3 catalyst is comparable to that on Pt/PANI, while the peak potential of MOR on the former is lowered by 180 mV as compared with the latter, suggesting a much higher catalytic activity of Pt/PANI-MoO 3 . The presence of MoO 3 may be responsible for the improvement of the catalytic properties through the co-synergistic effects of PANI and MoO 3 . [ABSTRACT FROM AUTHOR]

Tumor susceptibility gene 101 (TSG101) is a multi-functional gene involved in cell growth and proliferation in vertebrates. However, its role in the innate immune response of crustaceans remains unclear. Here, a TSG101 gene was identified in crayfish Procambarus clarkii with an open reading frame of 1320 bp that encoded a predicted 48.3-kDa protein highly homologous to those in other invertebrates. TSG101 mRNA was highly expressed in stomach and hepatopancreas, and its expression was induced significantly in different tissues (hemocytes, gills and intestine) by lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (poly I: C) with various expression patterns. Recombinant TSG101 protein was expressed in Escherichia coli , and a possible protein-protein interaction between TSG101 and hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) was explored by far-western blotting. RNA interference of TSG101 affected the gene expression of members of the Toll pathway. These results suggest that TSG101 is involved in the innate immune responses of P. clarkii . [ABSTRACT FROM AUTHOR]

Background & Aims Iron is an essential metal for fundamental metabolic processes, but little is known regarding the involvement of iron in other nutritional disorders. In the present study, we investigated disordered iron metabolism in a murine model of hereditary tyrosinemia type I (HT1), a disease of the tyrosine degradation pathway. Methods We analysed the status of iron accumulation following NTBC withdrawal from Fah −/− mice, a murine model for HT1. Liver histology and serum parameters were used to assess the extent of liver injury and iron deposition. To determine the physiological significance of iron accumulation, mice were subjected to a low-iron food intake to reduce the iron accumulation. Mechanistic studies were performed on tissues and cells using immunoblotting, qRT-PCR, adenovirus transfection and other assays. Results Severe iron overload was observed in the murine model of HT1 with dramatically elevated hepatic and serum iron levels. Mechanistic studies revealed that downregulation and dysfunction of Tfr2 decreased hepcidin, leading to iron overload. The Fah −/− hepatocytes lost the ability of transferrin-sensitive induction of hepcidin. Forced expression of Tfr2 in the murine liver reduced the iron accumulation. Moreover, transcription factor Sp1 was downregulated and identified as a new regulator of Tfr2 here. Additionally, low-iron food intake effectively reduced the iron deposits, protected the liver and prolonged the survival in these mice. Conclusions Iron was severely overloaded in the HT1 mice via the Sp1/Tfr2/Hepcidin axis. The iron overload induced liver injury in the HT1 mice, and reduction of the iron accumulation ameliorated liver injury. Lay summary Primary and secondary iron overload is an abnormal status affecting millions of people worldwide. Here, we reported severe iron overload in a murine model of HT1, a disease of the tyrosine degradation pathway, and elucidated the mechanistic basis and the physiological significance of iron overload in HT1. These studies are of general interest not only with respect to secondary iron-induced liver injury in HT1 but also are important to elucidate the crosstalk between the two metabolic pathways. [ABSTRACT FROM AUTHOR]

Composite oxides (MoO 3 ) m SnO 2 ( m being the atomic Mo/Sn ratio) are prepared and employed as the promoter to Pt toward methanol electrooxidation reaction (MOR) in alkaline electrolyte. The Pt electrocatalysts supported on (MoO 3 ) m SnO 2 /C are comprehensively characterized by TEM, XRD, XPS and electrochemical techniques. Electrochemical measurements for MOR indicate that molybdenum-doped SnO 2 show much higher promotion effect to the catalytic performances of Pt than the undoped SnO 2 . The activities of Pt in Pt–(MoO 3 ) m SnO 2 /C catalysts are also much higher than those in commercial Pt/C catalyst. Among the series of Pt–(MoO 3 ) m SnO 2 /C catalysts, Pt–(MoO 3 ) 0.2 SnO 2 /C shows the highest catalytic performances. The mass-specific activity (MSA) and intrinsic activity (IA) of Pt in Pt–(MoO 3 ) 0.2 SnO 2 /C is ca . 3.0 and 3.5 times higher than those of Pt/C catalyst, respectively. The high content of Pt(II and IV) in the catalysts and the changes in Pt electronic structure are responsible for this improvement. These data suggest that the composite metal oxides (MoO 3 ) m SnO 2 are effective promoter to Pt toward MOR, which would be promising in designing new catalysts for high-performance alkaline direct methanol fuel cells and other technologies. [ABSTRACT FROM AUTHOR]