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This study investigated the influence of Cd (25 µM) on Zn accumulation in a hyperaccumulating (HE) and a non-hyperaccumulating (NHE) ecotype of Sedum alfredii Hance at short-term supply of replete (Zn5, 5 µM) and excess (Zn400, 400 µM) Zn. Cd inhibited Zn accumulation in both ecotypes, especially under Zn400, in organs with active metal sequestration, i.e. roots of NHE and shoots of HE. Direct biochemical Cd/Zn competition at the metal-protein interaction and changes in transporter gene expression contributed to the observed accumulation patterns in the roots. Specifically, in HE, Cd stimulated SaZIP4 and SaPCR2 under Zn5, but downregulated SaIRT1 and SaZIP4 under Zn400. However, Cd downregulated related transporter genes, except for SaNRAMP1 , in NHE, irrespective of Zn. Cadmium stimulated casparian strip (CSs) development in NHE, as part of the defense response, while it had a subtle effect on the (CS) in HE. Moreover, Cd delayed the initiation of the suberin lamellae (SL) in HE, but stimulated SL deposition in NHE under both Zn5 or Zn400. Changes in suberization were mainly ascribed to suberin-biosynthesis-related genes and hormonal signaling. Altogether, Cd regulated Zn accumulation mainly via symplasmic and transmembrane transport in HE, while Cd inhibited both symplasmic and apoplasmic Zn transport in NHE. [Display omitted] • Cd reduced Zn accumulation in locations where both HE and NHE actively sequester them. • Cd/Zn competition in transporters led to less symplasmic uptake in both ecotypes. • Different endodermal development contributed to different radial transport of Zn and Cd. • SOD plays significant role in Zn-induced development of casparians strips. • The effect of Cd on suberin lamellae development was dependent on exogenous Zn level. [ABSTRACT FROM AUTHOR]

Red wine grape color and quality decrease substantially at the late stages of ripening in warm climates because of anthocyanin degradation; however, the underlying mechanism remains unclear. We analyzed the anthocyanin metabolite and transcriptome profiles of Yan73 grape berries from two vintages using HPLC-ESI-MS/MS and RNA-sequencing technologies. The results showed that anthocyanins in Yan73 grape skin and flesh were significantly degraded at the late stages of ripening in both vintages. Moreover, non-methylated anthocyanins were degraded at a higher rate than the methylated anthocyanins. The protocatechuic acid (i.e., possible anthocyanin degradation product) concentration increased significantly in Yan73 skin and flesh at the late stages of ripening. However, the expression of anthocyanin biosynthesis-related structural genes and MYBA1 was upregulated in Yan73 skin and flesh at the late stages of ripening, indicating an increase in the anthocyanin synthesis capacity. Enzyme activity and qRT-PCR assays revealed that peroxidase and polyphenol oxidase activities and the VvPrx31 expression level increased in Yan73 skin and flesh at the late stages of ripening, suggesting they may function in the anthocyanin degradation. The β-glucosidase activity was higher only in Yan73 grape flesh at the late stages of ripening. These findings clarify the pre-harvest anthocyanin degradation in grape berries. [Display omitted] • Anthocyanins in Yan73 grape were markedly degraded at late ripening stage in 2 years. • Non-methylated anthocyanins were degraded at a higher rate than the methylated ones. • Anthocyanin synthesis genes were highly expressed in Yan73 grape at late ripening stage. • Peroxidase, polyphenol oxidase activities increased in Yan73 grape at late ripening stage. • One peroxidase gene, Prx31, was highly expressed in Yan73 grape at late ripening stage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly dispersed Pd-Mn 3 O 4 catalyst was constructed by limited pyrolysis oxidation strategy. • Strong metal-support interaction effect between Pd and Mn 3 O 4 make the surface electron rich. • Strong metal-support interaction effect was conducive to catalyse propane degradation. Adjusting the interaction between dual active components for enhancing volatile organic compounds (VOCs) degradation is an effective but still challenging means of air pollution control. Herein, a limited pyrolysis oxidation strategy was adopted to prepare Pd-Mn 3 O 4 spinel catalysts with uniform morphology and active component dispersion. Among these, 1.08Pd-Mn 3 O 4 presented the highest catalytic efficiency with a T 90 value of 240 °C, which was 94 °C lower than that of Mn 3 O 4. Characterization and density functional theory (DFT) calculation results revealed that the strong metal-support interaction (SMSI) effect between Pd and Mn 3 O 4 promoted the redistribution of surface charges, thus strengthening the oxidation-reduction ability of the active sites. Moreover, the SMSI effect led to a better migration of surface oxygen species, and boosted the generation of active surface oxygen species. Simultaneously, the Pd catalyst further reduced the energy barrier in the initial stage of the dehydrogenation of propane. Overall, this study provided a novel design strategy for dual active components catalysts with SMSI effect and extended the application of these catalysts in the important field of VOCs elimination. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient CoMoS catalysts have been successfully synthesized with TOF values up to 1.3 × 10-3 s−1 in HDS reaction, which is nearly two times higher than that of the conventional Al 2 O 3 -loaded catalysts. • The abundant CoMoS active sites on the catalyst are derived from the use of novel Co 5 Mo 10 polyoxometalate (POMs), and the intimate combination of the Co-O-Mo on the precursor ensures the generation of Co-promoted MoS 2 sites. • The high sulfidation and high dispersion of active metals is attributed to the "weakening metal-support interaction" property from the inert hollow mesoporous carbon sphere (HMCS) supports. • HMCS support with large specific surface area and appropriate pore size act as the nanoreactors facilitating the concentration of reactants within the pore channel and adequate contact with the active site. The rational design of high sulfurization and abundant CoMoS active phases catalysts is the key to drive the industrialization of hydrodesulfurization (HDS). Herein, we prepared a nano-catalyst with well-dispersed and numerous CoMoS active sites through confining Co 3 (II)[Co 2 (III)Mo 10 O 38 H 4 ] (Co 5 Mo 10) polyoxometalates (POMs) molecules with high Co/Mo ratio in hollow mesoporous carbon spheres (HMCS). On the one hand, POMs acted as pre-assembled molecular platform can build and regulate the structure of active phases by precisely adjusting the Co/Mo atomic ratio at molecular level. Meanwhile, the intimate interaction of Co-Mo on the POMs precursor also ensures that the Co species mainly exists as Co-promoted MoS 2 active phase after the sulfidation process, thus the highly efficient synergism of the bimetals can be fully utilized in the reaction. On the other hand, the mesoporous carbon sphere with homogeneous pore size and high specific surface area can effectively confine the growth of the catalyst to disperse the active metals. The weakening metal–metal interaction property of such inert support enables the S-Co 5 Mo 10 /HMCS-10 catalyst to realize higher sulfurization, shorter slab length and higher stacking number. In addition, the abundant mesopores and high pore capacity of support greatly facilitate the mass transfer process and provide sufficient space for the HDS reaction as the nanoreactor. The unique combination of POMs and HMCS enabled the S-Co 5 Mo 10 / H 10 catalyst to achieve up to 99.2% conversion of dibenzothiophene (DBT) after 4 h of HDS reaction, while obtaining a TOF value of 1.3 × 10−3 s−1 (calculated when keeping the low conversion at 42% after 0.5 h of reaction). The structural orientation of the POMs precursors to the active phases of HDS catalysts was investigated using various characterization methods, and the structure–activity relationship between the catalytic performance and the sulfide active phases was also revealed in this work. [ABSTRACT FROM AUTHOR]

[Display omitted] • MnO 2 treated by urea-H 2 O 2 exhibits great photocatalytic propane oxidation activity. • H 2 O 2 treatment increase active sites to thermal catalytic performance. • The photocatalytic performance improvement is related to photogenerated electrons. • A new photothermal synergetic catalysis mechanism was proposed. Photothermal catalysis has an advantage in effective and economical elimination technology of volatile organic compounds (VOCs) in the ascendant. Herein, various surface defect engineering routes were adopted to enhance the low-temperature propane oxidation of δ-MnO 2. Compared to reducing etchants urea and vitamin C, δ-MnO 2 treated with urea - H 2 O 2 exhibited an excellent thermal (T 90 = 240 ℃) and photothermal (T 90 = 196 ℃) activities of propane oxidation. Urea - H 2 O 2 treatment provided high concentration of Mn4+ and surface-active oxygen (Mn4+-O sur) species as surface-active sites, and produced numerous oxygen vacancies to improve charge separation and superoxide species generation capacity. Thus, the photothermal conversion efficiency and low-temperature reducibility were remarkably enhanced. Furthermore, the photothermal synergistic catalytic mechanism was proposed based on in-situ diffuse reflectance infrared Fourier transform spectroscopy and control experiments. The strategy here offered insight into the rational design of efficient transition catalysts, and in-depth understanding of the photothermal catalytic VOCs removal mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and environmental-friendly preparation of hydrodesulfurization catalysts. • Synchronization and riveting of MoS 2 nanoflakes in mesoporous carbon framework for efficient hydrodesulfurization catalyst. • NaCl and thiourea as hard template and sulfidizing agent, respectively. • Well-defined Evans-Showell polyoxometalate as precursor. Two new mesoporous carbon-supported Co-Mo hydrodesulfurization catalysts with different Co contents have been successfully prepared by one-step vacuum freeze-drying, followed by calcination under a nitrogen atmosphere and washing. Evans-Showell polyoxometalate (NH 4) 6 [Co 2 Mo 10 O 38 H 4 ]·7H 2 O was used as the Co-Mo precursor instead of the conventional precursors, and the obtained catalysts were structurally characterized by various technologies, including X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, H 2 temperature programmed reduction, CO temperature programmed desorption and low temperature N 2 adsorption-desorption isotherm. The results show that MoS 2 particles (4.6 nm and 4.5 slabs) are homogeneously dispersed in the mesoporous carbon framework with a narrow pore size distribution centered at 3.7 nm. The catalysts were evaluated by the hydrodesulfurization of dibenzothiophene, and the results show that the dibenzothiophene conversion, overall pseudo-first order rate constant and turnover frequency can reach 95 %, 5.4 × 10−6 mol g −1 s−1 and 6.1 × 10−3 s−1 at 300 °C, respectively, indicating higher catalytic activity than previously reported catalysts. The higher proportion of the CoMoS active phase can account for the higher catalytic activity. By using in situ-produced sodium chloride crystals and thiourea as hard templates and sulfidizing agents respectively, this study opens a new avenue for the simple and environmentally friendly preparation of hydrodesulfurization catalysts with the synchronization and riveting of MoS 2 nanoflakes and 3D mesoporous carbon frameworks. [ABSTRACT FROM AUTHOR]

Owing to super nucleophilicity and coordination ability, the trivacant polyoxoanion [PW 9 O 34 ]9- was selected as multidentate O- ligands to chelate Ni2+ promoters for fabricating and regulating NiWS synergetic active sites at atomic scale. Thereby achieving ultra-dispersion of Ni species, high Ni/W ratio, and atomic-scale Ni-W proximity, which enableed PW 9 to have a preferable hydrodesulfurization performance. [Display omitted] • Controlled synthesis of a novel catalyst derived from lacunary POMs with an efficient NiWS active phases. • The rich electronic and vacant characteristics of [PW 9 O 34 ]9- synergistically induce the self-assembly of superior Ni/W precursor. • The structure of impregnating solution is revealed by coupling spectrum and X-ray single crystal analyses. • High concentration and high-efficiency synergism of NiWS active phases are derived from lacunary POMs. • The as-prepared catalyst exhibits excellent HDS performance compared with conventional Ni–W catalyst. Efficient catalysts with abundant NiWS active phases for hydrodesulfurization (HDS) were prepared based on structural diversity as well as unique electrostatics property of lacunary Keggin polyoxometalates (POMs). Owing to super nucleophilicity and coordinative ability, the trivacant Keggin [PW 9 O 34 ]9- (PW 9) can accurately capture and anchor Ni2+ promoters into its skeleton to form nanosized Ni x @PW 9 molecule in impregnating solution, thereby achieving ultra-dispersion of Ni promoters, high Ni/W ratio, and atomic-scale Ni–W proximity. The superior structure of Ni x @PW 9 promoted the simultaneous reduction and sulfuration of Ni and W species, thus obtaining shorter slab length, less stacking number, highly efficient synergism, and high concentration of NiWS active phases. Therefore, the resulted S-NiPW 9 /Al 2 O 3 catalyst exhibits efficient HDS activity for dibenzothiophene (DBT) removal compared to that of reference catalysts prepared from monovacant [PW 11 O 39 ]7- (PW 11), saturated [PW 12 O 40 ]3- (PW 12), and conventional oxide precursors. The structure-directing effects of oxidic POM precursors on the texture and performance of HDS active phases were revealed by employing a variety of characterization methods, including transmission Fourier transform infrared (TS-FTIR), attenuated total reflectance Fourier transform infrared (ATR-FTIR), ultraviolet–visible spectroscopy (UV–Vis), single crystal X-ray diffraction, H 2 temperature programmed reduction (H 2 -TPR), CO adsorbed Fourier transform infrared spectroscopy (IR/CO), X-ray photoelectron spectroscopy (XPS) and high-resolution transmission electron microscopy (HRTEM). This POMs-based molecular methodology opens a new avenue to better understand the evolution behavior of precursors and the formation mechanism of active species during the preparation of catalysts. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Improving the rate capability of transition metal oxides is of great important for the development of high-performance electrodes for supercapacitors. Here, a novel strategy of hydrogenation to enhance the electron transfer rate of manganese dioxide (MnO 2) is proposed. Detailed preparative parameters (i.e. hydrogenation temperature and time) are systematically investigated. The hydrogenated MnO 2 (H-MnO x) exhibits modified crystal phase/surface structures and increased electrical conductivity. The prepared H-MnO x exhibits high specific capacitance (640 mF cm−2 at current density of 1 mA cm−2), good rate capability (89.6% of capacitance retained from 1 to 10 mA cm−2), and good cycling stability (84.6% retention after 1000 cycles). The high specific capacitance is ascribed to the unique interconnected ultrathin nanosheets structure, which could not only provide porous channels for electrolyte infiltration to offer sufficient electrode/electrolyte interface, but also shorten the ions diffusion distance inside the active material. The good rate capability could be attributed to the good conductivity of the H-MnO x nanosheets, which was confirmed by the DFT calculation. These results highlight the importance of hydrogenation as a facile yet effective strategy to improve the rate capability of transition metal oxides for supercapacitors. [ABSTRACT FROM AUTHOR]

Highly active hydrodesulfurization (HDS) catalysts have been prepared successfully through a molecular approach using well-defined Strandberg P Mo Ni polyoxometalates (POMs) as superior precursors. The hand-picked POMs significantly facilitated not only the formation of highly dispersed Ni Mo species but also the formation of abundant and accessible NiMoS active sites at lower sulfidation temperatures, thereby resulting in a remarkable activity improvement in comparison with reference catalysts prepared with conventional precursors. Characterization results revealed the multidirecting effects of the POMs component and structure on the morphology and composition of the species in the NiMoS active phase and the evolution of precursors during the catalyst preparation simultaneously. The bottom-up POMs-based preparation methodology provides a better understanding of HDS catalyst structure and performance, thus further shedding light on the rational design and controllable fabrication of efficient HDS catalysts. [ABSTRACT FROM AUTHOR]

Background The goals of this study were to validate the role of c-Jun N-terminal kinase (JNK) activation in skin flap apoptosis in a rat model of abdomen skin ischemia and/or reperfusion (IR) and to compare the protective effect of SP600125 and hydrogen-rich saline in skin IR injury. Methods Male Sprague–Dawley rats were divided into five groups: one sham surgery group and four surgery groups. Before undergoing 3 h of IR management, the surgery groups were treated with normal saline (IR), dimethyl sulfoxide, SP600125 (SP), and hydrogen-rich saline (H). On the third postoperative day, blood perfusion of the flap was measured using Laser Doppler flowmeters. Hematoxylin and eosin staining was used to observe morphologic changes. Early apoptosis was observed using TdT-mediated dUTP-X nick end-labeling staining. pASK-1, pJNK, Bcl-2, and Bax were examined by immunodetection. Caspase-3 activity was also measured 24 h after reperfusion. Results Compared to the IR group and the dimethyl sulfoxide group, the SP group and the H group had larger skin flap survival area, more blood perfusion and lower levels of caspase-3 activity. The SP and the H groups had high expression levels of Bcl-2 and low expression levels of pASK-1 and pJNK. Bax was significantly decreased in the SP group. In addition, cell apoptosis was decreased in both the sham surgery and the H groups. Conclusions IR-induced JNK phosphorylation was reduced by SP600125, indicating that JNK mediates the apoptosis pathways in rat skin. In the SP and the H groups, the apoptotic factors measured showed similar expression levels, indicating that JNK inhibition during IR may be associated with H-mediated protection against skin IR apoptosis. [ABSTRACT FROM AUTHOR]

Chronic exposure to low-levels of organophosphate (OP) compounds, such as chlorpyrifos (CPF), induces oxidative stress and could be related to neurological disorders. Hydrogen has been identified as a novel antioxidant which could selectively scavenge hydroxyl radicals. We explore whether intake of hydrogen-rich water (HRW) can protect Wistar rats from CPF-induced neurotoxicity. Rats were gavaged daily with 6.75 mg/kg body weight (1/20 LD 50 ) of CPF and given HRW by oral intake. Nissl staining and electron microscopy results indicated that HRW intake had protective effects on the CPF-induced damage of hippocampal neurons and neuronal mitochondria. Immunostaining results showed that the increased glial fibrillary acidic protein (GFAP) expression in astrocytes induced by CPF exposure can be ameliorated by HRW intake. Moreover, HRW intake also attenuated CPF-induced oxidative stress as evidenced by enhanced level of MDA, accompanied by an increase in GSH level and SOD and CAT activity. Acetylcholinesterase (AChE) activity tests showed significant decrease in brain AChE activity after CPF exposure, and this effect can be ameliorated by HRW intake. An in vitro study demonstrated that AChE activity was more intense in HRW than in normal water with or without chlorpyrifos-oxon (CPO), the metabolically-activated form of CPF. These observations suggest that HRW intake can protect rats from CPF-induced neurotoxicity, and the protective effects of hydrogen may be mediated by regulating the oxidant and antioxidant status of rats. Furthermore, this work defines a novel mechanism of biological activity of hydrogen by directly increasing the AChE activity. [ABSTRACT FROM AUTHOR]

• Glucose sensors based on the helical long-period grating (HLPG) coupling to mode LP 16. • The surface of the optical fiber is modified by poly (4-vinylphenylboronic acid). • The sensor has a linear response to glucose (0.18 ~ 3 mg/mL) at pH 7.4. A glucose sensor based on a helical long-period grating (HLPG) coupling to a high-order cladding mode is demonstrated, which is composed of an optical fiber with the fiber surface modified by poly (4-vinylphenylboronic acid). The sensor has a linear response to glucose (0.18 ~ 3 mg/mL) with a sensitivity of 1.115 nm·(mg/mL)−1 at pH 7.4 and 3.259 nm·(mg/mL)−1 at pH 9, respectively. [ABSTRACT FROM AUTHOR]