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TiO2 (B) nanosheets/GO (graphene oxide) hybrids are considered to be outstanding performance photocatalysts for high efficiency of H2 evolution. However, they still suffer severe challenges during the synthetic processes, such as a large amount of the capping agents adhering on the surface and easy occurrence of aggregation. To figure out these obstacles, Ar plasma treatment as a modified method in this study not only enable the TiO2 (B) nanosheets distributed uniformly on the GO sheets but also engineer defects within TiO2 (B) nanosheets to significantly improve the photocatalytic activity for the water splitting. The hydrogen evolution rate of the TiO2-x (B)/GO sheets is 1.4 times higher compared with that of original TiO2 (B)/GO sheets without Ar plasma treatment. The improved photocatalytic properties were owing to the synergetic effects of oxygen vacancies and the heterojunction between GO and TiO2 (B), which can promote the visible light utilization and accelerate separation and transportation of photogenerated electron-holes. This study can provide a facile pathway to prepare the two-dimensional hybrid photocatalysts with high photocatalytic H2 activity.

Background: PTEN has been raised its role in kidney homeostasis. Previously, we demonstrated that podocyte-specific knock-in of PTEN alleviated albuminuria and glomerular sclerosis in mice with diabetic kidney disease. However, the role of PTEN in acute kidney injury (AKI) and repair remains unknown. Methods: Renal proximal tubular cells (RPTC)-specific PTEN overexpression mice were established by crossing PTENfl-stop-fl mice with Ggt1-Cre mice. Mass spectrometry (MS) of proteomics was performed among sham, BIRI, and BIRI+PTEN-OE mice .Findings PTEN was downregulated in serum and renal tubular cells ( RTC ) in mice subjected to I/R injury and repair. The concentration of serum PTEN was negatively correlated with serum creatinine. RPTC-specific PTEN overexpression alleviated I/R-induced renal injury and apoptosis, and subsequent renal fibrosis. MS analysis revealed that differentially expressed proteins (DEPs) between BIRI+PTEN-OE and BIRI mice were significantly enriched in phagosome, PI3K/AKT, and HIF-1 signaling and showed that CHMP2A was significantly changed among DEPs enriched in autophagy. Consistently, PTEN was downregulated in I/R-treated HK-2. PTEN deficiency accumulated autophagosome-bound LC3-II and P62 and inhibited autolysosome formation via downregulating CHMP2A, resulting in aggravated cell injury and apoptosis of HK-2 subjected to I/R, while overexpression of PTEN exhibited opposite effect. However, silencing CHMP2A abolished the effect of PTEN overexpression on autophagy flux and cell damage in I/R-treated HK-2. Interpretation: Our work implicates a critical role of PTEN in regulating CHMP2A-mediated phagosome closure in autophagy flux in RTC subjected to I/R-induced renal injury and repair, and provides evidence for PTEN/CHMP2A might serve as a novel target for I/R-AKI therapy. Funding: This work was supported by grants from the National Natural Science Foundation of China (No. 81770727), GDUPS (2017), Key Project of Guangzhou Science Technology and Innovation Commission (201804020054), the Natural Science Foundation of Guangdong (2021A1515011376), and Science and Technology Planning Project of Guangdong Province (2017A010103041). Declaration of Interest: None to declare. Ethical Approval: All animal experiments were approved by the Institutional Animal Care and Use Committee of Nanfang Hospital.

In this study, we raised silkworm larvae from the fifth instar with a modified diet of copper or silver nanoparticles (NPs) combined with mulberry leaves. Silkworm larvae growth was characterized according to larvae weight, survival rate, cocooning and silk glands microstructures. Cu or Ag element distributions in their tissues were examined with inductively couple plasma mass spectroscopy. The properties of silkworm silks were investigated with Fourier transform infrared (FTIR) and amino acid analyses, thermogravimetric and quasi-static tensile tests. Our results depicted a primary concentration distribution map of Cu or Ag element in silkworm larva tissues by the modified diet, and Cu or Ag NPs had slightly negative influences on the growth of the silkworm larvae. Results from FTIR spectra and amino acid analyses showed that the Cu or Ag NPs slightly inhibited the β-sheet conformation transition and promoted the crystallization of silk protein. Furthermore, copper or silver NPs obviously enhanced the thermal stability and mechanical properties of silkworm silk with a coupling competitive mechanism. This study expands our ability to obtain distinctive reinforced silkworm silks in a green and effective way and to gain an elementary comprehension of nano-bio interactions between a model organism, Bombyx mori silkworm, and metallic nanoparticles. Keywords: Bombyx mori silkworm, Metallic nanoparticles, Silk gland, Silk fibre, Metallic element distribution, Mechanical property

The radial sand ridges (RSRs) in the southwestern Yellow Sea off the Jiangsu Coast, East China have been intensively studied at least since 1975. Despite decades of studies, the provenance of the RSR sediments remains uncertain. In this study, the Nd-Sr isotopic and REE geochemical compositions of residual sediments (i.e., the acid-insoluble fractions) were investigated to determine the provenance of the RSR sediments. The Nd isotopic composition, PAAS-normalized REE patterns and characteristic parameters (e.g., Sm/Nd, (La/Sm)N, (Gd/Yb)N) were merely associated with source rocks but not with particle sorting while the Sr isotopic composition and REE contents of residual sediments were affected by particle sorting in addition to source rocks. The onshore RSR sediments originated mainly from mixing of the fine-grained sediments from various parts of the offshore RSR in terms of REE geochemical and isotopic analyses. Isotopic and REE geochemical comparison further reveals that the RSRs off the Jiangsu Coast were fed chiefly by the dispersal of surface sediments from the Yangtze River Mouth. Surface sediments from the Yangtze River Mouth were directly dispersed to the RSRs along the Jiangsu Coast and significantly affected the seaward part of the offshore RSR and the old Yellow River Delta area by a northward branch of the Changjiang Diluted Freshwater Plume. Only minor quantities of surface sediments from the modern Yellow River Mouth were introduced into the RSRs by the Jiangsu Coastal Current and mainly contaminated the landward part of the offshore RSR area. Our findings highlighted the potential of the Nd isotopes with REE geochemistry to trace the provenance of coastal sediments.

Increasing attention has been attracted on biodegradable and eco-friendly biocomposites. In this paper, biodegradable poly(butylene succinate) (PBS) biocomposites reinforced by spun silkworm silk fabric were fabricated using the hot-press technique, and their mechanical properties were studied by uniaxial tension and three-point bending tests, dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM) observations. The results demonstrated that the tensile, flexural, and dynamic mechanical properties of PBS biocomposites are pronouncedly improved with the increase in the silk fiber content. There exists an optimal value of the fiber content, ∼60 wt%, which leads to the comprehensively superior properties. We also found that spun silk fabric showed a remarkable reinforcing effect on the mechanical properties of PBS biocomposites, though surface treatment had not been performed to the silk. This study is valuable for design of silk-based biodegradable biocomposites with enhanced mechanical properties.

The two common expressions of near-bed sediment flux (also called erosion and deposition flux) in terms of sediment carrying capacity and bed shear stress are unified in this study. A behavior-oriented formula to calculate coastal bathymetry evolution caused by coastal engineering on a muddy coast is also developed based on the unified expression. Compared with the other common behavior-oriented formulas on a muddy coast, the vertical suspended sediment distribution and near-bed sediment exchange mechanism are considered, and the formula has the advantage of calculating both bed siltation and erosion distribution. The formula is applied to simulate the local morphology change resulting from the siltation-promoting works at the mouth of the Yangtze River estuary of China. A comparison between the measurement and the calculated results of other common formulas shows that the morphology change caused by the project is well reproduced, and the behavior-oriented formula can be used to predict the coastal bathymetry evolution caused by coastal engineering on muddy coast.

Hydrodynamics and the estuarine turbidity maximum (ETM) were investigated along the Deepwater Navigation Channel (DNC) in the North Passage (NP) of the Changjiang River Estuary (CRE) during spring tides in March (dry season) and July (wet season) in 2016. The along-channel water current, salinity, and suspended sediment concentration (SSC) were measured and compared with a study undertaken in 2012. Results show that the magnitude of SSC in the dry season was significantly larger than that in the wet season in 2016, which was contrary to the results obtained in 2012 and the commonly held understanding that SSC is much higher in wet seasons than dry seasons in this region. Despite the abnormal magnitude of the SSC, the spatial distribution agreed with that of the 2012 observations, and corresponded to the salinity distribution. By analysing the bottom sediment flux and sediment transport over a flood-ebb tidal cycle, the immediate cause of the abnormal SSC magnitudes was found. In the dry season, the resuspension fluxes were more than doubled and tidal pumping terms were significantly larger than of those in the wet season, thus indicating that the resuspension effect was much stronger and able to bring more sediment into the water. Although the strong resuspension effect in the dry season was partly due to a slightly higher tidal dynamic, it was mainly due to the availability of sufficient sediment for resuspension, as induced by the strong cold-air front several days previous. On the contrary, the weak resuspension effect under a similar tidal dynamic in the wet season, was associated with insufficient sediment availability as a result of the limited influence of the typhoon in 2016. In addition, the quantity of sediments available for resuspension influenced the mobile suspension (MS) events of the ETM. Local resuspension and along-channel advection were both important in SSC variation processes and the effect of along-channel advection was more distinct when there was insufficient sediments for resuspension.

Epidermal growth factor receptor (EGFR) that has been over-expressed in many different types of cancers has become logical targets for both diagnosis and therapy. Herein, we report an electrochemical peptide-based biosensor for the detection of EGFR, in which ferrocene moiety modified peptide ligands that are specific to EGFR were immobilized on gold electrode through Au–S interaction. Upon the binding of peptide ligands with EGFR, complex formation changes occurred on the electrode surface, which resulted in current increase. The amplitude of the current increase displayed a linear relationship with logarithm of the EGFR concentrations in the range of 1.0 × 10−6–1.0 × 10−10 g L−1, with a detection limit of 3.7 × 10−11 g L−1. The proposed method has been applied for determination of EGFR in diluted human serum samples with satisfied results.

Two C-rich DNA strands are employed to fabricate the intermolecular i-switch: strand 1 with thiol at the 5′-terminus immobilized on the gold electrode through the thiol–Au interaction, and ferrocene (Fc)-labeled strand 2 that hybridizes with strand 1 to form an i-switch nanostructure. In neutral or basic aqueous solution, the i-switch is present in the form of an extended duplex that makes Fc far away from the electrode; a weak faradaic current is obtained, so-called “OFF” state. While in the slight acidic condition, an obvious signal is detected from Fc which approaches the electrode due to the formation of the i-motif, so‐called “ON” state. The faradaic current has a linear relationship with the pH value in the range of 5.8–8.0. Keywords: i-Motif, i-Switch, pH, Electrochemistry, DNA hybridization

Zn 0.95− x Co 0.05 Cu x O (ZCCO, where x = 0, 0.005, 0.01 and 0.015) thin films were deposited on Si (1 0 0) substrates by pulsed laser deposition technique. Crystal structures, surface morphologies, chemical compositions, bonding states and chemical valences of the corresponding elements for ZCCO films were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and X-ray photoelectron spectroscopy (XPS). XRD and FESEM results indicate that crystallite sizes of the highly (0 0 2)-oriented ZCCO films slightly decrease with increasing Cu content. When the Cu content increases from 0 to 0.015, Zn 2 p 3/2 , Co 2 p , Cu 2 p 3/2 and O 1 s peaks of the ZCCO film shift towards higher or lower binding energy regions, and the reasons for these chemical shifts are investigated by fitting the corresponding XPS narrow-scan spectra. Both in-plane and out-of-plane magnetization-magnetic field hysteresis loops of the ZCCO films reveal that all the films have room temperature ferromagnetisms (RTFMs). The conceivable origin of the RTFM is ascribed to the combined effects of the local structural disorder resulted from (Co 2+ , Cu 2+ , Cu 1+ )-cations which substitute Zn 2+ ions in the ZnO matrices, ferromagnetic coupling between coupled dopant atoms caused by Co 2+ (3 d 7 4 s 0 ) and Cu 2+ (3 d 9 4 s 0 ) spin states, and exchange interactions between the unpaired electron spins originating from lattice defects induced by Cu doping in the Zn 0.95 Co 0.05 O matrices.

Ba0.9Sr0.1TiO3 (BST) thin films were deposited on fused quartz and Pt/TiN/Si3N4/Si substrates by radio frequency magnetron sputtering technique. Microstructure and chemical bonding states of the BST films annealed at 700 °C were characterized by field emission scanning electron microscopy, X-ray photoelectron spectroscopy, glancing angle X-ray diffraction and Raman spectrum. Optical constants including refractive indices, extinction coefficients and bandgap energies of the as-deposited BST film and the BST films annealed at 650, 700 and 750 °C, respectively, were determined from transmittance spectra by envelope method and Tauc relation. Dielectric constant and remnant polarization for the BST films increase with increasing annealing temperature. Leakage current density-applied voltage (J–V) data indicate that the dominant conduction mechanism for all the BST capacitors is the interface-controlled Schottky emission under the conditions of 14 V

Radio frequency magnetron sputtered Ba"0"."6"5Sr"0"."3"5TiO"3 (BST) thin films were etched in CF"4/Ar/O"2 plasma by magnetically enhanced reactive ion etching technique. The etching characteristics of BST films were characterized in terms of microstructure and electrical properties. Atomic force microscopy and X-ray diffraction results indicate that the microstructure of the etched BST film is degraded because of the rugged surface and lowered intensities of BST (100), (110), (111) and (200) peaks compared to the unetched counterparts. Dielectric constant and dielectric dissipation of the unetched, etched and postannealed-after-etched BST film capacitors are 419, 346, 371, 0.018, 0.039 and 0.031 at 100kHz, respectively. The corresponding dielectric tunability, figure of merit and remnant polarization are 19.57%, 11.56%, 17.25%, 10.87, 2.96, 5.56, [email protected]/cm^2, 2.32 and [email protected]/cm^2 at 25V, respectively. The leakage current density of 1.75x10^-^4 A/cm^2 at 15V for the etched BST capacitor is over two orders of magnitude higher than 1.28x10^-^6 A/cm^2 for the unetched capacitor, while leakage current density of the postannealed-after-etched capacitor decreases slightly. It means that the electrical properties of the etched BST film are deteriorated due to the CF"4/Ar/O"2 plasma-induced damage. Furthermore, the damage is alleviated, and the degraded microstructure and electrical properties are partially recovered after the etched BST film is postannealed at 923K for 20min under a flowing O"2 ambience.

The novel 2D snowflake-like ZnO structures have been self-assembly synthesized on SiO2/Si substrate coated with Pt strips by thermal evaporation of Zn power. Scanning electron microscopy, X-ray diffraction, transmission electron microscopy measurements showed that the snowflake-like ZnO possesses the perfect six-fold symmetric single-crystalline wurtzite structure. The room-temperature photoluminescence spectrum revealed a strong ultraviolet emission band at 382 nm. The possible growth process was also discussed. It was found that the deposition of thin layer of Pt strips is important for the formation of 2D snowflake-like ZnO structures.

A modified sol–gel method was used to fabricate (Pb 0.25 Ba x Sr 0.75− x )TiO 3 (PBST) thin films with x = 0.05,0.1,0.15 and 0.2 on Pt/TiO 2 /SiO 2 /Si substrate. The structure, surface morphology, dielectric and tunable properties of PBST thin films were investigated as a function of barium content ( x ). X-ray diffraction and scanning electron microscopy analysis showed that we could get pure PBST perovskite phase and relative fine density thin films with smooth surface. It was found that the crystal lattice constant, grain size, room temperature dielectric constant, dielectric loss and tunability of Ba solutionizing PST thin films increased with the increase in Ba content. For (Pb 0.25 Ba 0.2 Sr 0.55 )TiO 3 thin film, it had the highest dielectric constant of 1390 and the largest tunability of 80.6%. The figure of merit parameter reached a maximal value of 28.9 corresponding to the (Pb 0.25 Ba 0.05 Sr 0.7 )TiO 3 thin film, whose dielectric constant, dielectric loss and tunability measured at 1 MHz were 627, 0.024 and 69.4%, respectively.

Highly transparent conductive Dy 2 O 3 doped zinc oxide (ZnO) 1– x (Dy 2 O 3 ) x nanocrystalline thin films with x from 0.5% to 5% have been deposited on glass substrate by pulsed laser deposition technique. The structural, electrical and optical properties of Dy 2 O 3 doped thin films were investigated as a function of the x value. The experimental results show that the Dy concentration in Dy-doped ZnO thin films has a strong influence on the material properties especially electrical properties. The resistivity decreased to a minimum value of 5.02 × 10 −4 Ω cm with x increasing from 0.5% to 1.0%, then significantly increased with the further increasing of x value. On the contrary, the optical direct band gap of the (ZnO) 1– x (Dy 2 O 3 ) x films first increased, then decreased with x increasing. The average transmission of Dy 2 O 3 doped zinc oxide films in the visible range is above 90%.

In this paper, in-situ electrospinning method was presented to directly fabricate semiconductor (Ag2S or Cu2S) nanostructures on the outer surfaces of polyacrylonitrile (PAN) nanofibers. PAN/metallic salt composite fibers were electrospun firstly as precursors, after UV irradiation photoreduction and the treatment of H2S gas, Ag2S or Cu2S nanostructures can be obtained on the outer surface of PAN nanofibers. The interactions between the polymer and metallic ions are believed to be the main factor in determining the position of metallic ions based on the electrospun nanofibers. Transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) are used to characterize the products.

In this work, composite nanostructures of BiFeO 3 (BFO) and poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] copolymers were fabricated using porous anodic aluminum oxide (AAO) templates by sol–gel and vacuum infiltration methods. Scanning electron microscope (SEM) and high-resolution transmission electron microscopy (HRTEM) were employed to investigate the morphology of composite nanostructures. It was found that a double-layer nanostructure with inner P(VDF-TrFE) copolymers for high insulating property and outer BFO nanotubes for mechanical supporting. The leakage current density of BFO/P(VDF-TrFE) composite nanostructures is four orders of magnitude lower than that of BFO under ±8 MV/m. It is suggested that the facile approach has great potential in multiferroic devices.