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Cubic ZrV 2 O 7 thin films have been synthesized by sol-gel spin-coating method. The influences of annealing temperatures on the phase composition and morphology of ZrV 2 O 7 thin films were investigated using XRD, SEM, and EDX. Negative thermal expansion (NTE) and optical performances of cubic ZrV 2 O 7 thin films were analyzed using variable temperature XRD and UV–Vis spectroscopy. Results indicate that as-deposited ZrV 2 O 7 thin films have an amorphous structure with smooth and dense surface. Cubic ZrV 2 O 7 thin films were prepared after heat treatment at 720 °C for 1 h. It was found that the thin films contained V 2 O 5 impurity with the Zr: V = 1:2 precursor solution. Pure cubic ZrV 2 O 7 thin films were fabricated with the Zr: V = 1.75:2 precursor solution. Cubic ZrV 2 O 7 thin films show isotropic NTE in the temperature range of 100–700 °C. The coefficients of thermal expansion (CTEs) of ZrV 2 O 7 films along the a , b , and c axes are −6.88 × 10−6 °C−1, and the volumetric and linear CTEs are −20.56 × 10−6 °C−1 and -6.85 × 10−6 °C−1, respectively. The transmittance of cubic ZrV 2 O 7 thin film is approximately 80 %. [ABSTRACT FROM AUTHOR]

Orthorhombic Sc 2 (MoO 4) 3 nanofibers have been prepared by ethylene glycol assisted electrospinning method. The effects of annealing temperature, precursor concentration, spinning distance and solvent on the preparation of Sc 2 (MoO 4) 3 nanofibers were characterized by XRD, SEM, HRTEM, EDX and high-temperature XRD. XRD analysis shows as-prepared nanofibers are amorphous. Orthorhombic Sc 2 (MoO 4) 3 nanofibers can be fabricated after annealing at different temperatures in 500–800 °C for 2 h. The crystallinity of Sc 2 (MoO 4) 3 nanofibers improves and the nanofiber diameter decreases gradually as the annealing temperature increases. However, the nanofiber structure was destroyed at the annealing temperature above 700 °C. Higher precursor concentration results in a slight increase of diameter and decrease in destroying temperature of Sc 2 (MoO 4) 3 nanofibers. Spinning distance also affects the diameter of nanofibers, and the nanofiber diameter decreases as the distance increases. One-dimensional orthorhombic Sc 2 (MoO 4) 3 nanofibers exhibit anisotropic negative thermal expansion. In 25–700 °C, the coefficients of thermal expansion (CTE) of α a , α b and α c are −5.81 × 10−6 °C−1, 4.80 × 10−6 °C−1 and -4.33 × 10−6 °C−1, and the α l of Sc 2 (MoO 4) 3 nanofibers is −1.83 × 10−6 °C−1. [ABSTRACT FROM AUTHOR]

Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films have been synthesized using the sol-gel spin coating. Influences of post-annealing temperatures on crystal structure, morphology, negative thermal expansion (NTE) and optical performances of the thin films were studied using XRD, SEM, XPS, high-temperature XRD and UV–Vis–NIR spectrophotometer. XRD and SEM results show that as-prepared thin film is in an amorphous state with a smooth and dense surface. Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films were obtained after post-annealing in 550–750 °C. The higher the annealing temperature in 550–750 °C, the better the crystallinity of orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films. In addition, the grain size of the In 0.5 Sc 1.5 Mo 3 O 12 thin film also grows as the annealing temperature increases. The resulting orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films exhibit anisotropic NTE. Its volumetric coefficient of thermal expansion (CTE) is −3.44 × 10−6 °C−1, while the CTEs in a -, b - and c -axis directions are −4.70 × 10−6 °C−1, 5.37 × 10−6 °C−1, and -4.10 × 10−6 °C−1 in 25–700 °C, respectively. In addition, the transmittance of orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 thin films post-annealed at 750 °C is around 87.75 %–95.03 %. [ABSTRACT FROM AUTHOR]

Orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 nanofibers were prepared by electrospinning followed by a heat treatment. The effects of post-annealing temperatures on the phase composition, microstructure and morphology were investigated by XRD, SEM, HRTEM and XPS. Negative thermal expansion (NTE) behaviors of the In 0.5 Sc 1.5 Mo 3 O 12 nanofibers were analyzed by high-temperature XRD. Results indicate that the as-prepared In 0.5 Sc 1.5 Mo 3 O 12 nanofibers show an amorphous structure with smooth and homogeneous shape. The average diameter of the as-prepared In 0.5 Sc 1.5 Mo 3 O 12 nanofibers is around 515 nm. Well crystallized orthorhombic In 0.5 Sc 1.5 Mo 3 O 12 nanofibers could be prepared after post-annealing at 550 °C for 2 h with an average diameter of about 192 nm. The crystallinity of In 0.5 Sc 1.5 Mo 3 O 12 nanofibers gradually improved with the increase of annealing temperature. However, too high post-annealing temperature leads to a damage of sample's fiber structure. The high-temperature XRD results reveal that In 0.5 Sc 1.5 Mo 3 O 12 nanofibers show an anisotropic NTE, and the coefficients of thermal expansion (CTEs) along a -axis and c -axis were −5.95 × 10−6 °C−1 and -3.54 × 10−6 °C−1, while the one along b -axis is 5.61 × 10−6 °C−1. The volumetric CTE of In 0.5 Sc 1.5 Mo 3 O 12 nanofibers is −3.90 × 10−6 °C−1 and the linear one is 1.3 × 10−6 °C−1 in 25–700 °C. [ABSTRACT FROM AUTHOR]

Since the aggregate structure influence the mechanical response of mixture and its monitoring signal, this study mainly advance the integration of gradation theory and sensor testing methods from the micro-scale analysis. Based on sphere parking theory, the upper and lower limit of weighted average size in gradations were determined from the point of densest/loosest state respectively. Three skeletons according to the weighted average size criterion were designed for comparatively analysis of their stability. Moreover, a smart rock(SR)sensor was embedded for monitoring and a skeleton-sensor coupling model was further established to reveal the mechanism of skeleton's evolution. Results show that although the weighted average size criterion is based on pure sphere assumption, it still works when comes to aggregates with real angular shapes. Key attributes of different skeletons can be captured and identified by the embedded sensor from the point of particle's sliding and rearrangement. Thus,apart from currant indices such as stress/strain etc,the movements data including acceleration and angular acceleration also shows a huge potential possibility in pavement monitoring in the future. • Muti-scale conversion in modelling based on HCP lattice was proposed. • Pure sphere parking theory is verified in angular aggregate skeletons. • Damage characteristic is revealed by skeleton-sensor coupling analysis. • Application of SR sensor is validated in capturing skeletons' micro-states. [ABSTRACT FROM AUTHOR]

Microcystin-leucine-arginine (MC-LR), a cyclic potentially carcinogenic hepatotoxin, occurs frequently in aquatic habitats worldwide and seriously threatens ecosystem and public health. Limited effectiveness of physicochemical treatments to remove MC-LR from drinking water has led to a search for alternative cost-effective and environment friendly biodegradation strategies. Obtaining MC-degrading bacteria and understanding their MC-degrading mechanisms are outstanding challenges. Here, a novel indigenous bacterium named Sphingopyxis sp. YF1 with a high efficient capacity for MC-degradation was successfully isolated from eutrophic Lake Taihu. Through integrating mass spectrometer and multi-omics analyses accompanied by functional verification of certain genes and proteins, a complete MC-degradation pathway was firstly identified, in which MC-LR was sequentially degraded into linearized MC-LR, tetrapeptide, Adda, phenylacetic acid, and finally potential product CO 2. Some specific proteins such as microcystinase, linearized-microcystinase, tetrapeptidease and PAAase responsible for this pathway were identified. This study pioneeringly demonstrated that MC-LR can be completely degraded through natural remediation processes and revealed a significant potential for MC-LR biodegradation in both natural environment and engineered systems. Image 1 • New MC-degrading genes and products were explored through a multi-omic approach. • A complete MC degradation pathway was identified. • A novel bacterium with high MC-degrading rate was isolated from Lake Taihu. • Proteomics data of MC-degrading bacteria were obtained for the first time. • A series of key enzymes responsible for detoxifying MC-LR were identified. [ABSTRACT FROM AUTHOR]

Microcystis blooms and their secondary metabolites microcystins (MCs) occurred all over the world, which have damaged aquatic ecosystems and threatened public health. Techniques to reduce the Microcystis blooms and MCs are urgently needed. This study aimed to investigate the algicidal and inhibitory mechanisms of a red pigment prodigiosin (PG) against the growth and MC-producing abilities of Microcystis aeruginosa (M. aeruginosa). The numbers of Microcystis cells were counted under microscope. The expression of microcystin synthase B gene (mcyB) and concentrations of MCs were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and enzyme linked immunosorbent assay (ELISA) methods, respectively. The inhibitory effects of PG against M. aeruginosa strain FACHB 905 with 50% algicidal concentration (LC 50) at 120 h was 0.12 μg/mL. When M. aeruginosa cells exposed to 0.08 μg/mL, 0.16 μg/mL, 0.32 μg/mL PG, the expression of mcyB of M. aeruginosa was down-regulated 4.36, 8.16 and 18.51 times lower than that of the control at 120 h. The concentrations of total MC (TMC) also were 1.66, 1.72 and 5.75 times lower than that of the control at 120 h. PG had high algicidal effects against M. aeruginosa , with the activities of superoxide dismutase (SOD) initially increased and then decreased after 72 h, the contents of malondialdehyde (MDA) increase, the expression of mcyB gene down-regulation, and MCs synthesis inhibition. This study was first to report the PG can simultaneously lyse Microcystis cells, down-regulate of mcyB expression and inhibit MCs production effectively probably due to oxidative stress, which indicated PG poses a great potential for regulating Microcystis blooms and MCs pollution in the environment. Image 1 • PG has high algicidal effects against Microcystis aeruginosa. • PG down-regulates mcyB expression and reduces MCs production effectively. • The algicidal and inhibitory mechanisms of PG against Microcystis sp. are related to oxidative stress. PG poses a great potential for regulating Microcystis blooms and MCs pollution by simultaneously lysing M. aeruginosa and inhibiting the synthesis of MCs. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Kai-Xin-San, an ancient formula composed of Ginseng Radix et Rhizoma, Polygalae Radix, Acori Tatarinowii Rhizoma and Poria, was frequently applied for major depression disorders for thousands of years. However, its molecular mechanism has not clearly been investigated. Aim of the study We aimed to reveal the action mechanism of KXS on anti-depression on inducing neuronal differentiation on PC12 cells. Materials and methods A chemically standardized water extract of KXS was applied onto cultured PC12 cells in determining its effect on neurotransmitter regulation enzymes and neurite outgrowth. Results Single KXS treatment showed obvious changes in the expression of neurofilament and neurotransmitter regulation enzymes, which in parallel to treatment of nerve growth factor (NGF). Although KXS by itself did not show significant inductive effect on neurite outgrowth of PC12 cells, KXS could potentiate the NGF induced neurite outgrowth. Among the three ratios, K-652 showed the most powerful effect and cAMP-dependent pathway might play the major role. Conclusions KXS might exert the anti-depressant-like action of be inducing neuronal differentiation, which supported the clinically usage of this decoction. [ABSTRACT FROM AUTHOR]

The increasing production of microcystin-LR (MC-LR) causing animal and human health issues is found in eutrophic water bodies, marine habitats and desert environments. The health threat posed by MC-LR has led to the establishment of World Health Organization's water guideline value of 1 μg/mL. Combating this has increased the search for cost-effective approach to degrade MC-LR. The study aimed to optimize the MC-degrading environmental factors of bacterial community YFMCD4. Response surface methodology (RSM) was employed to evaluate the influence of varying temperatures, pH and initial MC-LR concentration on the biodegradation efficiency of MC-LR by bacterial community YFMCD4. The optimal MC-LR biodegradation environmental factors were found to be 30 °C, pH 7 and 2 μg/mL initial MC-LR. The biodegradation rate reached 100% after 10 h. YFMCD4 mainly consisted of genera Alacligenes , Sphingobacterium and Pseudomonas using High-throughput pyrosequencing technology. The mlrA gene encoding MlrA enzyme considered most important for MC-LR biodegradation was obtained from YFMCD4. Data demonstrated that the bacterial structure and biodegradation efficiency of YFMCD4 varied with the change of environmental factors including temperature, pH and MC-LR concentrations. RSM is considered a good method to examine the optimal biodegradation environmental conditions for MC-LR. To date, RSM and High-throughput pyrosequencing technology are employed to optimize the biodegradation conditions (30 °C, pH 7 and 2 μg/mL initial MC-LR) and analyze the structure of bacterial community for the first time. • RSM was used to optimize MC-LR biodegradation conditions by YFMCD4 for the first time. • Varying temperatures, pH and MC-LR concentrations influenced MC-LR biodegradation. • Structure of YFMCD4 was analyzed by high-throughput pyrosequencing technology. • mlrA and mlrD homologues genes were amplified from YFMCD4. [ABSTRACT FROM AUTHOR]

The effect of crop straw return on C 2 –C 5 non-methane hydrocarbon (NMHC) emissions from agricultural soils is investigated using a laboratory-controlled incubation of agricultural soils amended with crop straw for a period of 56 days. The average emission fluxes of total C 2 –C 5 NMHCs from amended agricultural soils are 304 and 173 ng kg −1 h −1 under non-flooded and flooded conditions, respectively. Alkenes are the principal emitted C 2 –C 5 NMHCs from amended agricultural soils, where a predominance of ethene, propene and 1-butene together shared 65% and 59% of the total C 2 –C 5 NMHCs under non-flooded and flooded conditions, respectively. The emissions rates of the above top three alkenes and the total C 2 –C 5 alkenes from amended agricultural soils under non-flooded conditions are one to four times those under flooded conditions, and these average values are 14–89 and 5–34 times those in their corresponding control treatments, respectively. These results imply that straw return contributes substantially to the emissions of light alkenes from agricultural soils, particularly under non-flooded conditions. The high correlation between microorganisms and C 2 –C 5 NMHC fluxes from amended agricultural soils suggest that microbes play an important role in C 2 –C 5 NMHC emissions from straw-amended agricultural soils. A rough estimate indicates that crop straw return could contribute insignificantly to global C 2 –C 5 hydrocarbon budgets. [ABSTRACT FROM AUTHOR]