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An earthquake of magnitude M5.7 occurred in Yamutu village, Songyuan City, Jilin Province, NE China (45°16′12″N/124°42′35″E) on May 28, 2018, with a focal depth of 13 km. The epicenter is located at the intersection of the Fuyu/Songyuan-Zhaodong Fault, Second Songhua River Fault and Fuyu North Fault which lies northwest of Tancheng-Lujiang Fault (Tan-Lu Fault). The earthquake-induced widespread liquefaction structures and ground surface fissures within 3 km from the epicenter, caused serious disasters to the local surroundings. The visible liquefied structures include sand volcanoes, liquefied sand mounds, sand dikes and sand sills. Sand volcanoes can be divided into sand volcano with a crater, sand volcano without a crater and water volcano (no sand). Other soft-sediment deformation structures (SSDS) induced by the earthquake include deformation lamination, load and flame structures, deformation folds, dish structures, convolute bedding and water-escape structures. The formation process of the sand volcanoes comprises three stages: (1) building up excess pore-fluid pressure in the liquefied layer, (2) cracking of the low-permeable overlying layer, and (3) mixture of sand-water venting out of the ground surface. During the upward movement, the liquefied sand is injected into the low-permeable layer to form sand veins, sand sills and various types of deformation structures. Vertical distribution of seismic liquefaction structure can be divided into four zones: the thoroughly liquefied zone, the lower liquefied zone with SSDS, the upper liquefied zone with SSDS, and the ground surface liquefied zone. The liquefaction occurred at a burial depth of 2–5 m, and the thickness of liquefied sand is 2 m. NE-SW (35°–215°) trending compressive stress is possibly the seismogenic trigger of the Songyuan M5.7 earthquake that caused the fault (Fuyu/Songyuan-Zhaodong Fault) to reactivate. The study of the Songyuan seismic liquefaction structures gives insight into the prediction of modern earthquakes and disaster-prone areas. Meanwhile it provides abundant basic material for studying earthquake-induced SSDS in both ancient and modern sediments. The research is obviously of great significance to reveal that the northern Tan-Lu Fault has entered a stage of active seismic activity since the twenty-first century. [ABSTRACT FROM AUTHOR]

Xylanase is widely used for the degradation lignocellulosic biomass as an important accessory enzyme. But productive hydrolysis of the recalcitrant lignocellulose also requires for applicable pretreatment with environmental friendliness. Meanwhile, the complicated industrial processes also demand for catalytically efficient enzymes with more resistance to both pH and heating conditions, which barely exist for the wild types. In this study, the dominant mutant H51K/Q118A from Gloeophyllum trabeum derived GtXyn10 (WT) was obtained by directed evolution. Compared to the WT, apart from the impressive pH resistance from pH 1.0–9.0, the dominant mutant H51K/Q118A also exhibited higher specific activity (2.5-fold; 2510 vs. 1010 U/mg), higher catalytic efficiency (2.4-fold; 460 vs. 190 mL/s‧mg), and better thermostability (with t 1/2 at 80 °C extend by 10 min). When 'Seawater + Feton' pretreatment was applied, the lignin clearance rate reached 62.5%, 86.6% higher than that of feton pretreatment (33.5%). After pretreatment of 'Seawater + Feton', Compared with the cellulase-only treatment (159 μmol/g), synergistic hydrolysis with both H51K/Q118A and cellulase (236 μmol/g) increased the fermentable sugar yields from bagasse by 48.4%. In combination with the optimized pretreatment and synergistic hydrolysis of the modified xylanase and cellulase, the fermentable sugar production for green bio-energy was realized with efficiency. [Display omitted] • An efficient xylanase with improved properties was obtained by directed evolution. • Steric hindrance elimination was a possible mechanism for catalytic enhancement. • 'Seawater + Feton' pretreatment promoted the removal of lignin in bagasse. • Synergistic hydrolysis (H51K/Q118A + cellulase) realized the optimal degradation. • Biomass utilization for fermentable sugars was optimized by combined strategies. [ABSTRACT FROM AUTHOR]

Melanoma differentiation-associated gene 5 (MDA5) is a member of the retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs) family and plays a pivotal role in the anti-viral innate immune response. As RIG-I is absent in chickens, MDA5 is hypothesized to be important in detecting viral nucleic acids in the cytoplasm. However, the molecular mechanism of the regulation of chicken MDA5 (chMDA5) expression has yet to be fully elucidated. With this in mind, a ∼2.5 kb chMDA5 gene promoter region was examined and PCR amplified to assess its role in immune response. A chMDA5 promoter reporter plasmid (piggybac-MDA5-DsRed) was constructed and transfected into DF-1 cells to establish a Piggybac-MDA5-DsRed cell line. The MDA5 promoter activity was extremely low under basal condition, but was dramatically increased when cells were stimulated with polyinosinic: polycytidylic acid (poly I:C), interferon beta (IFN-β) or Infectious Bursal Disease Virus (IBDV). The DsRed mRNA level represented the promoter activity and was remarkably increased, which matched the expression of endogenous MDA5. However, Infectious Bronchitis Virus (IBV) and Newcastle disease virus (NDV) failed to increase the MDA5 promoter activity and the expression of endogenous MDA5. The results indicated that the promoter and the Piggybac-MDA5-DsRed cell line could be utilized to determine whether a ligand regulates MDA5 expression. For the first time, this study provides a tool for testing chMDA5 expression and regulation. [ABSTRACT FROM AUTHOR]

A nonenzymatic amperometric glucose sensor was established based on the electrocatalytic oxidation of nanoporous gold (NPG) toward glucose. The NPG electrode was prepared by a facile, rapid one-step square-wave oxidation reduction cycle (SWORC) within 5 min. The prepared NPG electrode had high roughness, excellent electrocatalytic activity toward glucose electrooxidation and was characterized by scan electron microscopy (SEM), atomic force microscope (AFM) and cyclic voltammetry (CV). The CV was also used to evaluate the electrochemical response of the NPG electrode to the glucose oxidation in 0.01 mol L −1 NaOH solution. Under the optimal conditions, the NPG electrode showed a good linear relationship between the current response signal and the glucose concentrations in a range from 2 μmol L −1 to 1.375 mmol L −1 and 1.375 mmol L −1 to 15 mmol L −1 with a detection limit of 0.5 μmol L −1 (S/N = 3). In addition, the nafion was selected as the protective film to enhance specificity of the developed glucose biosensor, and the physiological levels of ascorbic acid (0.1 mmol L −1 ) and uric acid (0.02 mmol L −1 ) only had negligible interferences to the glucose detection. This new glucose sensor exhibited a fast amperometric response, high sensitivity and selectivity, and it was successfully used to detect the glucose in human serum sample with a satisfactory result. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline (Y3−x Tm x )Al5O12 (x =0, 0.18, 0.9, 1.5, 3) ceramics were fabricated by a solid-state reaction method using high-purity micrometer-sized powders. Tm-doped ceramics with an almost perfect pore-free structure and high transparency were obtained by advanced ceramic processing. The average grain size and grain boundary width were 15μm and 1nm, respectively. The Y2.82Tm0.18Al5O12 (6at.% Tm:YAG) ceramic slab (5mm×5mm×3.5mm) was end-pumped by a Ti:sapphire laser at 785nm and the maximum output power of 725mW was obtained with a slope efficiency of 36.2% at 2012nm. [Copyright &y& Elsevier]

Abstract: Highly transparent Tm3Al5O12 (TmAG) ceramics were fabricated by solid-state reaction and vacuum sintering. Densification, microstructure evolution, mechanical, thermal, and optical properties of the TmAG ceramics were investigated. Fully dense TmAG ceramic with average grain size of ∼15μm was obtained by sintering at 1780°C for 20h. The in-line transmittance was 80.5% at 2000nm. The absorption coefficients at 682nm and 785nm were 8.03cm−1 and 8.33cm−1, respectively. The Vickers hardness, the Young modulus, the bending strength, and the fracture toughness values were 15.14GPa, 343GPa, 230MPa, and 2.35MPam1/2, respectively. The thermal conductivity at room temperature was 3.3W/mK and the average linear thermal expansion coefficient from 20°C to 1000°C was 8.915×10−6 K. [Copyright &y& Elsevier]

• Associations between cadmium exposure and cellular immune responses were examined. • Prenatal cadmium exposure was associated with reduced T lymphocyte subsets and increased Th2 cytokines. • The effects of prenatal cadmium exposure on cellular immune responses primarily occurred in females. • No clear associations between children's concurrent cadmium exposure and cellular immune responses were observed. Experimental studies have demonstrated that cadmium exposure induces alterations on immune function, but epidemiological evidence is lacking. To examine the associations between prenatal and postnatal cadmium exposure and cellular immune responses among pre-school children. Pre-school aged children (n = 407) were followed from a prospective birth cohort study in Wuhan, China. Maternal urinary and children's plasma cadmium concentrations were measured as biomarkers of prenatal and postnatal cadmium exposure, respectively. Children's cellular immune responses were assessed by peripheral blood T lymphocyte subsets and plasma cytokines. Multivariable adjusted models were applied to estimate the associations of prenatal and postnatal cadmium exposure with T lymphocyte subsets and cytokines, and the effect modification by child gender were also examined. Maternal urinary cadmium was associated with reduced absolute counts of CD3+CD4+ cells (−12.45%; 95% CI: −23.74%, 0.40% for the highest vs. lowest quartile; p for trend = 0.045). Inverse associations of maternal urinary cadmium with %CD3+CD4+ cells and CD4+/CD8+ ratio were only observed among females (both p-interaction < 0.050); whereas an inverse association with absolute counts of CD3+CD8+ cells was only observed among males (p-interaction = 0.057). Positive associations of maternal urinary cadmium with %CD3+CD4+ cells, interleukin-4 (IL-4), and IL-6 were only observed among females, although there were no significant interactions. We observed no clear associations of children's plasma cadmium with T lymphocyte subsets and cytokines. Prenatal but not postnatal cadmium exposure was associated with sex-specific alterations on children's cellular immune responses. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop and examine supports for inquiry practices in computer-based learning environments (CBLEs). Two kinds of supports for inquiry practices were developed, namely cognitive and metacognitive prompts. We employed a multiple case study design to analyze students' metacognitive reactions to these two kinds of prompts and the fading effect on the regulation process using a sequential analysis technique. The results of this study indicate that the high level inquiry group performed not only more metacognitive actions of monitoring and evaluating, but also performed them in different sequences than the less successful students (the middle and low level inquiry groups) during the prompted inquiry tasks. The sequential analysis in this study identified the students' crucial learning patterns of successful inquiry practices in both the structured and guided inquiry stages. The findings can be used to explore the possible alignment between scaffolding and learning behaviors, and the mechanism of fading for inquiry-based learning in CBLEs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Chlorella sp. CN6 with high macular pigment (MP) production was isolated. • A four-stage continuous microalgal culture module was established for MP production. • MP concentration of CN6 through white light and blue LED irradiation was 8.16 g/L. • MP productivity in the continuous culture module was 7.28 mg/L/day for 10 days. • The MP recovery and purity were > 80 % and > 90 %, with a lutein: zeaxanthin of 4–5:1. This study established and investigated continuous macular pigment (MP) production with a lutein (L):zeaxanthin (Z) ratio of 4–5:1 by an MP-rich Chlorella sp. CN6 mutant strain in a continuous microalgal culture module. Chlorella sp. CN6 was cultured in a four-stage module for 10 days. The microalgal culture volume increased to 200 L in the first stage (6 days). Biomass productivity increased to 0.931 g/L/day with continuous indoor white light irradiation during the second stage (3 days). MP content effectively increased to 8.29 mg/g upon continuous, indoor white light and blue light-emitting diode irradiation in the third stage (1 day), and the microalgal biomass and MP concentrations were 8.88 g/L and 73.6 mg/L in the fourth stage, respectively. Using a two-step MP extraction process, 80 % of the MP was recovered with a high purity of 93 %, and its L:Z ratio was 4–5:1. [ABSTRACT FROM AUTHOR]

• MPC can set and harden normally at ≥−10 °C due to the double hydrolysis role of monoammonium phosphate and borax. • The reaction degree of MPC at room temperature ls lower than that at 0 °C. • The 2-hour compressive strength of the MPC (M/P = 4, B/M = 0.03 and W/C = 0.14) exceeds 15.0 MPa at −10 ± 2 °C. • The frozen MPC specimens were placed in room temperature, its compressive strength continues to increase due to the secondary reaction of MPC. Magnesia-phosphate cement (MPC) is considered the most promising inorganic cementing material for the rush-repair construction of concrete structures, pavements, and airport runways in negative-temperature environments. To prepare MPC repair materials that are suitable for negative temperatures, we studied and quantitatively analyzed the influences of dead-burned magnesia/phosphate (M/P), borax/dead-burned magnesia (B/M), and water/MPC (W/C) ratios on the reaction rate, early strength, and long-term strength of MPC prepared and cured at negative temperatures. The ice point of the mixed water decreased to −10 °C because of the double hydrolysis role of monoammonium phosphate and borax; therefore, MPC could set and harden at temperatures higher than −10 °C, and its 2 h compressive strength was > 15 MPa. The setting and reaction rate of MPC decreased steeply with decreasing temperature, and the 2 h compressive strength was as low as 3.0 MPa at − 20 ± 2 °C. The early strength of MPC enhanced on increasing the magnesium ion concentration in the MPC slurry, and the 2 h compressive strength of MPC at − 10 ± 2 °C increased by approximately 50% when the M/P ratio increased from 3 to 5. The early strength of MPC at negative temperatures was more sensitive to changes in the B/M and W/C ratios than at room temperature (20 ± 2 °C). When the temperature of the frozen MPC specimens that were maintained at − 10 ± 2 °C and − 20 ± 2 °C was increased to room temperature, the long-term strength of the MPC increased to approximately 80.9% and 67.6%, respectively, than that of the MPC maintained at room temperature, owing to the secondary reaction in the MPC. [ABSTRACT FROM AUTHOR]

High efficiency of microalgal growth and CO 2 fixation in a Photobioreactors (PBRs)/Raceway circulating (PsRC) system combined with alkaline-CO 2 capturing medium and operation was established and investigated. Compared with a pH 6 medium, the average biomass productivity of Chlorella sp. AT1 cultured in a pH 11 medium at 2 L min −1 circulation rate for 7 days increased by about 2-fold to 0.346 g L −1  d −1 . The maximum amount of CO 2 fixation and CO 2 utilization efficiency of Chlorella sp. AT1 could be obtained at a PBRs to Raceway ratio of 1:10 in an indoor-simulated PsRC system. A similar result was also shown in an outdoor PsRC system with a 10-ton scale for microalgal cultivation. Under the appropriate circulation rate, the stable growth performance of Chlorella sp. AT1 cultured by long-term semi-continuous operation in the 10-ton outdoor PsRC system was observed, and the total amount of CO 2 fixation was approximately 1.2 kg d −1 with 50% CO 2 utilization efficiency. [ABSTRACT FROM AUTHOR]

An alkali-tolerant Chlorella sp. AT1 mutant strain was screened by NTG mutagenesis. The strain grew well in pH 6–11 media, and the optimal pH for growth was 10. The CO 2 utilization efficiencies of Chlorella sp. AT1 cultured with intermittent 10% CO 2 aeration for 10, 20 and 30 min at 3-h intervals were approximately 80, 42 and 30%, respectively. In alkaline medium (pH = 11) with intermittent 10% CO 2 aeration for 30 min at 3-, 6- and 12-h intervals, the medium pH gradually changed to 10, and the biomass productivities of Chlorella sp. AT1 were 0.987, 0.848 and 0.710 g L −1 d −1 , respectively. When Chlorella sp. AT1 was aerated with 10% CO 2 intermittently for 30 min at 3-h intervals in semi-continuous cultivation for 21 days, the biomass concentration and biomass productivity were 4.35 g L −1 and 0.726 g L −1 d −1 , respectively. Our results show that CO 2 utilization efficiency can be markedly increased by intermittent CO 2 aeration and alkaline media as a CO 2 -capturing strategy for alkali-tolerant microalga cultivation. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the relationship between normal Fragile X mental retardation gene 1 ( FMR1 ) CGG repeat numbers and primary ovarian insufficiency (POI) occurrence or subsequent resumption of ovarian function. A total of 122 women with POI and 105 controls were followed up and analysed in our centre. The prevalence of premutation and intermediate range of FMR1 CGG repeats in Han Chinese women with POI was only 0.81% (1/122) and 1.64% (2/122), respectively. The risk of POI occurrence for less than 26 CGG repeats and 29 or more CGG repeats in allele1 (smaller allele) was significantly higher than that for 26–28 CGG repeats (odds ratio 13.50, 95% confidence interval: 3.21 to 56.77 and 6.32, 95% confidence interval: 2.49 to 16.09 respectively; both P < 0.001). No significant difference was found in the CGG repeat distribution (<26, 26–28, or ≥29) in FMR1 allele1 between POI cases whose ovarian function resumed and those whose ovarian function did not. It is suggested that the CGG repeat number in allele1, but not that in allele2 (longer allele), was significantly associated with POI occurrence ( P < 0.001). Fewer than 26 or more than 28 CGG repeats in FMR1 allele1 were both risk factors of POI occurrence. [ABSTRACT FROM AUTHOR]

Exposure to air pollution has been linked with altered immune function in adults, but little is known about its effects on early life. This study aimed to investigate the effects of exposure to air pollution during prenatal and postnatal windows on cell-mediated immune function in preschoolers. Pre-school aged children (2.9 ± 0.5 y old, n = 391) were recruited from a mother-child cohort study in Wuhan, China. We used a spatial-temporal land use regression (LUR) model to estimate exposures of particulate matter with aerodynamic diameters ≤2.5 μm (PM 2.5) and ≤10 μm (PM 10), and nitrogen dioxide (NO 2) during the specific trimesters of pregnancy and the first two postnatal years. We measured peripheral blood T lymphocyte subsets and plasma cytokines as indicators of cellular immune function. We used multiple informant models to examine the associations of prenatal and postnatal exposures to air pollution with cell-mediated immune function. Prenatal exposures to PM 2.5 , PM 10 , and NO 2 during early pregnancy were negatively associated with %CD3+ and %CD3+CD8+ cells, and during late pregnancy were positively associated with %CD3+ cells. Postnatal exposures to these air pollutants during 1-y or 2-y childhood were positively associated with IL-4, IL-5, IL-6, and TNF-α. We also observed that the associations of prenatal or postnatal air pollution exposures with cellular immune responses varied by child's sex. Our results suggest that exposure to air pollution during different critical windows of early life may differentially alter cellular immune responses, and these effects appear to be sex-specific. [Display omitted] • Effects of air pollution exposure on cell-mediated immune responses were estimated. • Late pregnancy air pollution exposures were positively related to %CD3+ cells. • Early pregnancy air pollution exposures were related to reduced %CD3+ and %CD3+CD8+ cells. • Postnatal air pollution exposures were positively associated with certain cytokines. • There were sex-specific associations between air pollution exposures and immune responses. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mutant from XYL10C_ΔN with improved catalytic activity was obtained through protein engineering. • Synergistic hydrolysis with the engineered xylanase and cellulase excelled other enzyme treatments. • Seawater immersion was helpful for biomass hydrolysis as chemical pretreatment. • Ramulus mori was converted into fermentable sugars with lower energy consumption. Biorefinery of Ramulus mori with lower energy consumption through improved enzyme and pretreatment strategies was reported. Directed evolution and saturation mutagenesis were used for the modification of xylanase, the yield of fermentable sugars and the degree of synergy (DS) were determined for different pretreatment (seawater/non-seawater) and enzyme treatment groups (xylanase/cellulase/co-treatment). The dominant mutant I133A/Q143Y of Bispora sp. xylanase XYL10C_ΔN was obtained with improved specific activity (1860 U/mg), catalytic efficiency (1150 mL/s∙mg) at 40 °C, and thermostability (T 50 increased by 7 °C). With the pretreatment of seawater immersion, the highest yield of fermentable sugars for Ramulus mori at 40 °C reached 199 μmol/g when hydrolyzed with cellulase and I133A/Q143Y, with the highest DS of 2.6; this was 4.5-fold that of the group hydrolyzed by cellulase alone with non-seawater pretreatment. Thus, bioconversion of reducing sugar from Ramulus mori was improved significantly at lower temperatures, which provides an efficient and energy-saving way for biofuel production. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient bagasse biorefinery with low energy consumption was realized. • A thermostable xylanase mutant was engineered for catalysis under mild conditions. • Seawater following steam explosion promotes the enzymatic hydrolyzation of bagasse. • Synergistic hydrolysis of high activity xylanase and cellulase was optimal. Lignocellulosic biorefining for producing biofuels poses technical challenges. It is usually conducted over a long time using heat, making it energy intensive. In this study, we lowered the energy consumption of this process through an optimized enzyme and pretreatment strategy. First, the dominant mutant M137E/N269G of Bispora sp. MEY-1 XYL10C_ΔN was obtained by directed evolution with high catalytic efficiency (970 mL/s∙mg) and specific activity (2090 U/mg) at 37 °C, and thermostability was improved (T 50 increased by 5 °C). After pretreatment with seawater immersion following steam explosion, bagasse was co-treated with cellulase and M137E/N269G under mild conditions (37 °C), the resulting highest yield of fermentable sugars reached 219 µmol/g of bagasse, 46% higher than that of the non-seawater treatment group, with the highest degree of synergy of 2.0. Pretreatment with seawater following steam explosion and synergistic hydrolysis through high activity xylanase and cellulase helped to achieve low energy degradation of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]