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Based on time-series satellite-retrieved records of the marine ecological environment from Aqua/MODIS, we investigated changes in the sea surface temperature (SST), photosynthetically active radiation (PAR), Secchi Disc depth (SDD), and chlorophyll-a concentration (Chla) in 12 Eurasian marginal seas from 2003 to 2014. Results showed that the SST increased in all 12 marginal seas, with the enclosed marginal seas (i.e., Black Sea, Baltic Sea, Japan Sea, Mediterranean Sea, and Persian Gulf) exhibiting relatively higher rates of increase. The PAR generally decreased, except in the European marginal seas, though not significantly. Similar to the changes in the SST, the SDD increased in all 12 marginal seas, with a maximum rate of 3.02%/year (or 0.25 m/year, p = 0.0003) found in the Persian Gulf. As expected, Chla generally decreased in the tropical marginal seas, but increased in the high-latitude marginal seas. The different relationships between SST and Chla changes indicate the complexity of global warming effects on marine phytoplankton in different marginal seas. [ABSTRACT FROM AUTHOR]

Purposes: We have previously reported that Ginsenoside Rb1 may effectively prevent HUVECs from senescence, however, the detailed mechanism has not demonstrated up to now. Recent studies have shown that sirtuin-1 (Sirt1) plays an important role in the development of endothelial senescence. The purpose of this study was to explore whether Sirt1 is involved in the action of Ginsenoside Rb1 regarding protection against H2O2-induced HUVEC Senescence. Methods and Results: Senescence induced by hydrogen peroxide (H2O2) in human umbilical vein endothelial cells (HUVECs) was examined by analyzing plasminogen activator inhibitor-1 (PAI-1) expression, cell morphology, and senescence-associated beta-galactosidase (SA-β-gal) activity. The results revealed that 42% of control-treated HUVECs were SA-β-gal positive after treatment by 60 µmol/L H2O2, however, this particular effect of H2O2 was decreased more than 2-fold (19%) in the HUVECs when pretreated with Rb1 (20 µmol/L) for 30 min. Additionally, Rb1 decreased eNOS acetylation, as well as promoted more NO production that was accompanied by an increase in Sirt1 expression. Furthermore, upon knocking down Sirt1, the effect of Rb1 on HUVEC senescence was blunted. Conclusions: The present study indicated that Ginsenoside Rb1 acts through stimulating Sirt1 in order to protect against endothelial senescence and dysfunction. As such, Sirt1 appears to be of particular importance in maintaining endothelial functions and delaying vascular aging. [ABSTRACT FROM AUTHOR]

The 26S proteasome plays a fundamental role in almost all eukaryotic cells, including vascular endothelial cells. However, it remains largely unknown how proteasome functionality is regulated in the vasculature. Endothelial nitric oxide (NO) synthase (eNOS)-derived NO is known to be essential to maintain endothelial homeostasis. The aim of the present study was to establish the connection between endothelial NO and 26S proteasome functionality in vascular endothelial cells. The 26S proteasome reporter protein levels, 26S proteasome activity, and the O-GlcNAcylation of Rpt2, a key subunit of the proteasome regulatory complex, were assayed in 26S proteasome reporter cells, human umbilical vein endothelial cells (HUVEC), and mouse aortic tissues isolated from 26S proteasome reporter and eNOS knockout mice. Like the other selective NO donors, NO derived from activated eNOS (by pharmacological and genetic approach) increased O-GlcNAc modification of Rpt2, reduced proteasome chymotrypsin-like activity, and caused 26S proteasome reporter protein accumulation. Conversely, inactivation of eNOS reversed all the effects. SiRNA knockdown of O-GlcNAc transferase (OGT), the key enzyme that catalyzes protein O-GlcNAcylation, abolished NO-induced effects. Consistently, adenoviral overexpression of O-GlcNAcase (OGA), the enzyme catalyzing the removal of the O-GlcNAc group, mimicked the effects of OGT knockdown. Finally, compared to eNOS wild type aortic tissues, 26S proteasome reporter mice lacking eNOS exhibited elevated 26S proteasome functionality in parallel with decreased Rpt2 O-GlcNAcylation, without changing the levels of Rpt2 protein. In conclusion, the eNOS-derived NO functions as a physiological suppressor of the 26S proteasome in vascular endothelial cells. [ABSTRACT FROM AUTHOR]

Abstract: A new photocatalyst, namely single-crystalline Bi5O7NO3 nanofibers, was prepared by a facile hydrothermal method in the presence of Triton X-100 and ammonia. Bi5O7NO3 possessing a crystalline sheet morphology could be dissolved and transformed into nanofibers by controlling the reaction time. Samples were characterized by X-ray diffraction, UV–vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and high resolution transmission electron microscopy. The Bi5O7NO3 nanofiber growth mechanism is discussed in detail. The band gap energy of the as-prepared Bi5O7NO3 photocatalyst was about 2.70–2.90eV. Results of first-principle density functional theory calculations confirmed that Bi5O7NO3 had a narrow band gap. They revealed that the conduction band bottom was predominantly composed of Bi 6s, Bi 6p, N 2p and O 2p orbitals, while the valence band (VB) top primarily consisted of Bi 6p, Bi 6s and O 2p orbitals. The as-obtained Bi5O7NO3 nanofibers showed good photocatalytic activity and stability for the degradation of Rhodamine B (RhB) under visible light irradiation, which may be ascribed to the highly mobile conduction band (CB) and VB charge carriers. [Copyright &y& Elsevier]

Abstract: ZnMoO4 with a rhombus sheet or flower-like structure, α-ZnMoO4 and needle-like ZnMoO4·0.8H2O were successfully synthesized by simple hydrothermal crystallization processes with citric acid. ZnMoO4·0.8H2O was easily synthesized in a shorter reaction time (2h) at a higher reactant concentration. It gradually transformed into ZnMoO4 with a monoclinic wolframite tungstate structure with an increased reaction time, and pure ZnMoO4 was obtained with a longer reaction time (8h). Citric acid (CA) played an important role in controlling the morphology of the as-obtained molybdates. The α-ZnMoO4 and ZnMoO4 were synthesized by heating ZnMoO4·0.8H2O at 130°C for 4h and 8h, respectively, under hydrothermal conditions. With transforming of ZnMoO4·0.8H2O to α-ZnMoO4 and further to ZnMoO4, the needle-like crystals gradually disappeared and were transformed into crystals with rhombus sheet morphology and then further to pentacle or flower-like crystals that can be ascribed to continuous splitting and growing of the rhombus sheets. [Copyright &y& Elsevier]

Polycarboxylate superplasticizers BMC-L and BMC-S were utilized as modifiers in the formulation of novel cement-based grouting materials. Indoor tests were conducted on 32 groups of cement slurries, varying by water–cement ratio (0.5:1 and 0.6:1) and modifier content (0, 2‰, 4‰, 6‰, 8‰, 10‰, 12‰, and 14‰), to test their density, funnel viscosity, water separation rate, and stone rate. Four groups of slurry modified with BMC-L were selected as the preferred slurry, and the apparent viscosity test, uniaxial, and triaxial compression test of the slurry stone body were conducted. The study investigated the influence of BMC-L on various properties of the slurry, including its apparent viscosity, uniaxial compressive strength, stress–strain relationships, shear strength parameters, and elastic modulus. Ultimately, the pore structure and phase composition of the slurry stone body were detected by Nuclear Magnetic Resonance (NMR) and X-ray Diffraction (XRD), and the impact of BMC-L on slurry performance was examined from a microstructural perspective. Results indicate that the two polycarboxylate superplasticizers exert minimal influence on the density and water separation rate of the slurry. Within the effective incorporation range of the polycarboxylate superplasticizer, increasing the dosage correlates with a decrease in both the stone rate and viscosity of the slurry. BMC-L significantly enhances the mechanical properties of the slurry stone body by promoting more complete cement hydration and reducing porosity. The uniaxial compressive strength of slurry stone body with a 6 ‰ BMC-L dosage reached 29.7 MPa after 7 days and 38.5 MPa after 28 days of curing, representing increases of 118.4% and 64%, respectively, compared to masonry with 0 BMC-L dosage. The shear strength parameters and elastic modulus of the slurry stone body also showed corresponding increases. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the new genetic etiologies of Rett syndrome (RTT) or Rett‐like phenotypes. Methods: Targeted next‐generation sequencing (NGS) was performed on 44 Chinese patients with RTT or Rett‐like phenotypes, in whom genetic analysis of MECP2, CDKL5, and FOXG1 was negative. Results: The detection rate was 31.8% (14/44). A de novo pathogenic variant (c.275_276ins AA, p. Cys92*) of KIF1A was identified in a girl with all core features of typical RTT. A patient with atypical RTT was detected having de novo GRIN1 pathogenic variant (c.2337C > A, p. Val793Phe). Additionally, compound heterozygous pathogenic variants of PPT1 gene were detected in a girl, who initially displayed typical RTT features, but progressed into neuronal ceroid lipofuscinoses (NCL) afterwards. Pathogenic variants in KCNQ2, MEF2C, WDR45, TCF4, IQSEC2, and SDHA were also found in our cohort. Conclusions: It is the first time that pathogenic variants of GRIN1 and KIF1A were linked to RTT and Rett‐like profiles. Our findings expanded the genetic heterogeneity of Chinese RTT or Rett‐like patients, and also suggest that some patients with genetic metabolic disease such as NCL, might displayed Rett features initially, and clinical follow‐up is essential for the diagnosis. [ABSTRACT FROM AUTHOR]

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Abstract Suspended particulate matter (SPM) is generally divided into inorganic (SPIM) and organic (SPOM) parts; they come from different sources, and have different impacts on the optical properties and/or water quality of lake. However, in a specific remote sensing process, they are not retrieved separately. Using in-situ data of 59 lakes along the middle and lower reaches of the Yangtze River (MLR-YR) in dry season (April) and wet season (August) in 2012, we first studied the absorption properties and sources of different SPM. On this basis, we proposed a workflow for simultaneously estimating SPIM and SPOM from satellite data. Our results are as follows: Bio-optical compositions of SPM in these eutrophic shallow lakes tempo-spatially varied greatly and were dominated by human-induced eutrophication. Phytoplankton contributed 18.42 ± 18.92% of SPIM and 26.22 ± 19.24% of SPOM in April 2012, but 30.4 ± 23.41% of SPIM and 47.03 ± 18.1% of SPOM in August 2012. The trophic state index explained 42.84% of SPOM variation in April 2012, and 54.64% in August 2012. Moreover, there were strong linear relationships between SPIM concentration and non-algal particle absorption coefficient (Pearson's r = 0.73 ; p < 0.01) and between SPOM concentration and phytoplankton absorption coefficient (r = 0.76 ; p < 0.01). Based on these results, SPIM and SPOM concentrations in the lakes along the MLR-YR could be retrieved from OLCI/Sentinel-3A satellite data, respectively. This study has a great significance for real-time monitoring and managing aquatic environment in various eutrophic and/or shallow lakes as a group. Graphical abstract Unlabelled Image Highlights • Lakes along the middle and lower reaches of Yangtze River were seriously eutrophic. • Suspended particle compositions were dominated by human-induced eutrophication. • Bio-optical compositions of suspended particles differed by trophic state index. • Monitoring suspended particle compositions using satellite data was achievable. [ABSTRACT FROM AUTHOR]

Abstract: Sr6Bi2O9 powders were synthesized by a sol–gel method using Bi(NO3)3·5H2O and Sr(NO3)2 as the starting materials and were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance spectrum (UV–vis DRS), Fourier transform infrared (FT-IR) spectrum and Raman spectrum. The as-prepared Sr6Bi2O9 powders showed an efficient photocatalytic activity in the decomposition of 4BS dye (a widely used azo dye) and 4-nitrophenol (4-NP, a priority pollutant) under visible light irradiation (λ >400nm). TA-PL analysis reveals that HOthe dominant photooxidant. The radical scavengers experiments indicated that the main active species was O2 − in the photocatalytic degradation of dye under visible irradiation. A possible photodegradation mechanism of organic pollutants by the visible light driven Sr6Bi2O9 was discussed. [Copyright &y& Elsevier]

Abstract: Most of tantalate photocatalysts are mainly synthesized by solid-state (SS) reaction methods and only show photocatalytic activity under UV light irradiation. Ta2O5 as a raw material shows an extremely high chemical stability, limiting its application to a few systems. A novel nanometer Bi3TaO7 photocatalyst was synthesized by a facile and low-cost sol–gel method using Ta2O5 and Bi(NO3)3·5H2O as the Ta and Bi sources, respectively. The as-obtained samples were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), UV–vis diffuse reflection spectroscopy (DRS) and Fourier transform infrared spectroscopy (FT-IR). The band gap energy of the as-obtained nanometer Bi3TaO7 photocatalyst was determined to be about 2.75–2.86eV. The Bi3TaO7 nanopowders show a strong adsorbability and a high visible-light photocatalytic activity for the degradation of 4BS, which can be ascribed to the surface physicochemical properties and structure of the Bi3TaO7 nanometer catalyst. The degradation of 4BS is attributed to the photocatalysis but not to the adsorption of 4BS on the as-prepared catalyst. [Copyright &y& Elsevier]