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Dextranases are hydrolases that exclusively catalyze the disruption of α−1,6 glycosidic bonds. A series of variant enzymes were obtained by comparing the sequences of dextranases from different sources and introducing sequence substitutions. A correlation was found between the number of amino acids in the 397–401 region and the hydrolytic process. When there were no more than 5 amino acids in the 397–401 region, the enzyme first hydrolyzed the dextran T70 to a low molecular weight dextran with a molecular weight of about 5000, then IMOs 1 1 IMOs: isomaltooligosaccharides. G: glucose, G2: maltose, G3: maltotriose, G4: maltotetraose, G5: maltopentaose, G6: maltohexaose, G7: maltoheptaose, IG2: isomaltose, IG3: isomaltotriose, IG4: isomaltotetraose, IG5: isomaltopentaose appeared in the system if the degradation continued, showing a clear sequential relationship. And when there are more than 5 amino acids in the 397–401 region, IMOs were produced at the beginning of hydrolysis and continue to increase throughout the hydrolytic process. At the same time, we investigated the enzymatic properties of the variants and found that the hydrolytic rate of A-Ca was 11 times higher than that of the original enzyme. The proportion of IMOs produced by A-Ca was 80.68%, which was nearly10% higher than the original enzyme, providing a new enzyme for the industrial preparation of IMOs. • One of the factors affecting the hydrolysis process of Aodex was determined. • Using sequence substitution method for molecular modification. • The hydrolysis rate of variant A-Ca increased by 11 times. • The proportion of IMOs produced by A-Ca was 80.68% which increased by nearly 10% compared to the WT. [ABSTRACT FROM AUTHOR]

Eye gaze plays a fundamental role in social interaction and facial recognition. However, interference processing between gaze and other facial variants (e.g., expression) and invariant information (e.g., gender) remains controversial and unclear, especially the role of facial information discriminability in interference. A Garner paradigm was used to conduct two experiments. This paradigm allows simultaneous investigation of the mutual influence of two kinds of facial information in one experiment. In Experiment 1, we manipulated facial expression discriminability and investigated its role in interference processing of gaze and facial expression. The results show that individuals were unable to ignore expression when classifying gaze with both high and low discriminability but could ignore gaze when classifying expression with high discriminability only. In Experiment 2, we manipulated gender discriminability and investigated its function in interference processing of gaze and gender. Participants were unable to ignore gender when classifying gaze with both high and low discriminability but could ignore gaze when classifying gender with low discriminability only. The results indicate that gaze categorization is affected by facial expression and gender regardless of facial information discriminability, whereas interference of gaze on facial expression and gender depends on the degree of discriminability. The present study provides evidence that the processing of gaze and other variant and invariant information is interdependent. [ABSTRACT FROM AUTHOR]

TiO 2 thin films prepared by atomic layer deposition (ALD) have attracted great attention due to the widespread application of the oxide as a promising charge storage material for lithium or proton batteries. In this work, we study TiO 2 film grown on Si substrates by atomic layer deposition with tetrakis (dimethylamino) titanium as metal precursor (TDMAT) and water vapour as an oxidant. The chemical composition and impurity content of the film as a function of growth temperature is studied by Ion Beam Analysis (IBA). D 2 O (99.8%) was used as oxidant to study the film growth to distinguish between hydrogen atoms originating from the water oxidant or the metal precursor. Combining ellipsometry with Rutherford Backscattering Spectrometry (RBS), Nuclear Reaction Analysis (NRA) and Elastic Recoil Detection Analysis (ERDA) reveals film density as a function of growth temperature. Atomic force microscopy (AFM) was used to characterize the film surface structure. By investigating the structural and compositional range of ALD TiO 2 films will open the new opportunities of application. In this work, we study TiO 2 film grown on Si substrates and bare Cu by atomic layer deposition with tetrakis (dimethylamino) titanium as metal precursor and water vapour as oxidant. The chemical composition and impurity content of the film as a function of growth temperature is studied by Ion Beam Analysis (IBA). D 2 O (99.8%) was used as oxidant to study the film growth to distinguish between hydrogen atoms originating from the water oxidant or the metal precursor. Combining ellipsometry with RBS, NRA, and ERDA reveals the film density as a function of growth temperature. Atomic force microscopy (AFM) was used to characterize the film surface structure.According to the composition and structure study, we here deposited ALD TiO 2 films on the copper as a function of deposition temperature, the Tafel polarization and electrochemical impedance spectroscopy (EIS) were used to study the anti-corrosion properties of ALD TiO 2 film coated on the copper in the 3.5% (0.6 M) NaCl solution. We proposed the H atoms in the TiO 2 films (100 °C) and the rough structure (225 and 300 °C) determine the corrosion behaviors. [Display omitted] • We explored the impurity content and in particular the carbon, nitrogen and hydrogen areal density in ALD TiO 2 film. • Isotope labelling confirmed that the vast majority of H atoms originated from the metal precursor. • The H atoms in the TiO 2 films (100 °C) could alleviate the barrier of charge transfer, high deposition temperature results in a high electron transfer resistance. [ABSTRACT FROM AUTHOR]

Fabrication of surfaces with capability of repelling both water and oil is badly needed. Meanwhile, the widespread use of nanomaterials has also attracted great interest in this field. In this paper, we provided novel methods to synthesize nano amorphous tungsten oxide coatings on Al-Mg metals. After modification with FAS-17, the surface could obtain excellent superamphiphobic abilities with lower sliding angles and higher contact angles to water and oil. In addition, outstanding anti-oil pollutant and low adhesion were obtained. Furthermore, the as-prepared superamphiphobic surfaces could survive 200 cm abrasion distance under 19.6 kPa pressure on 1000 grid SiC sandpaper. It should be noted that this coatings could obtain different colors in different temperature. Meanwhile, we found that the droplets with lower surface energy and low viscosity are easier to bounce than the droplets with high surface energy and high viscosity. So the simple procedure and excellent superamphiphobicity about fabricating colorful tungsten oxide coatings have great potential in protecting Al-Mg metal and have potential applied in signals which need to prevent wetting or pollution by water and oils. On one level, this method about synthesizing nano amorphous tungsten oxide also has more promising using in other fields. [ABSTRACT FROM AUTHOR]

With the need for fast and low-power radiation-hardened processors, advanced technology process is applied to obtain both high performance as well as high reliability. However, scaling down of the size of the transistor makes the transistor sensitive to outside disturbances, such as soft error introduced by the strikes of the cosmic neutron beams. Besides aerospace applications, such reliability should also be taken into consideration for the sub-100nm CMOS designs to ensure the robustness of the circuit. In such circumstances, several radiation-hardened flip-flops are designed and simulated under SMIC 40nm process. Simulation results show that with five aspects (performance, power, area, PVT variation and reliability) taken into consideration, TSPC-based DICE and TMR combined architecture has the best soft-error robustness in comparison with other radiation-hardened flip-flops, and the critical charge of such architecture is 490fC, which is 12.5X higher than the traditional unhardened flip-flop. [ABSTRACT FROM AUTHOR]

[Display omitted] • Equal TMDAT/water half cycles for ALD TiO 2 deposition give unexpected outcomes in the 100 °C-300 °C deposition temperature range. • Almost exclusively TiIV oxidation state throughout the 100 °C-300 °C temperature window. • Amorphous high H content, O/Ti < 2, valence band edge tails and gap states for 100 °C deposition temperature. • Lower H content crystalline films with O/Ti ∼ 2, no gap states for 225 °C deposition temperature and above. • Ligand exchange reaction byproducts confined to the oxide surface. • n – type oxides for all deposition temperatures. • Combined IBA and XPS are powerful tools to optimize ALD processes. Titania films prepared by atomic layer deposition attract great attention due to the widespread application of the oxide as a photocatalytic material, or more recently, as a promising charge storage material for lithium or proton batteries. We implement here advanced tools (Ion Beam Analysis and X-ray Photoelectron Spectroscopy, aided by Ellipsometry and X-ray Diffraction) to characterize films grown in the 100 °C-300 °C temperature window, using tetrakis(dimethylamino)titanium (TMDAT) as the metal precursor and water vapor as the oxidant. We examine the outcomes of the ALD process as a function of the deposition temperature, applying equal oxidant and precursor half-cycle time lengths, which contrasts with common deposition processes where the water half-cycle is considerably shorter than that of the metal precursor. Under the present ALD scheme, n -type conductive films are obtained where the oxidation state of titanium is overwhelmingly TiIV at all temperatures, while the hydrogen content (O/Ti ratio) varies considerably, from ∼ 15 at% (∼1.8) at 100 °C to ∼ 3 at% (∼2) at 300 °C. The ideality of the ALD process is discussed through the identification of nitrogen-containing molecules detected at the oxide surfaces. By extending the structural and compositional range of ALD titania films, new opportunities of application are expected to appear. [ABSTRACT FROM AUTHOR]

This paper proposed a novel voting ranking random forests (VRRF) method for solving hepatocellular carcinoma (HCC) image classification problem. Firstly, in preprocessing stage, this paper used bilateral filtering for hematoxylin-eosin (HE) pathological images. Next, this paper segmented the bilateral filtering processed image and got three different kinds of images, which include single binary cell image, single minimum exterior rectangle cell image, and single cell image with a size of n⁎n. After that, this paper defined atypia features which include auxiliary circularity, amendment circularity, and cell symmetry. Besides, this paper extracted some shape features, fractal dimension features, and several gray features like Local Binary Patterns (LBP) feature, Gray Level Cooccurrence Matrix (GLCM) feature, and Tamura features. Finally, this paper proposed a HCC image classification model based on random forests and further optimized the model by voting ranking method. The experiment results showed that the proposed features combined with VRRF method have a good performance in HCC image classification problem. [ABSTRACT FROM AUTHOR]

L-carnosine is a natural β-peptide compound with a wide range of important physiological functions. In this study, β-ester acyltransferase (As DmpA) can catalyze the reaction of β-amino acid methyl ester and β-amino acid methyl ester to form β-peptides and can also catalyze the reaction of β-amino acid methyl ester and L-histidine to form L-carnosine. Therefore, the reaction system will produce a variety of β-peptides, including L-carnosine. To solve this problem, the substrate specificity of As DmpA was improved by molecular modification to further increase the catalytic synthesis yield of L-carnosine. It was found that L341 W, L341K and L341R in saturated mutations increased the ability to catalyze L-carnosine synthesis. It was also found that the high proportion of L-histidine in the reaction system was conducive to the synthesis of L-carnosine. When the concentration ratio of L-histidine to β-alanine methyl ester hydrochloride is 140:10, the conversion rate of L-carnosine can reach more than 90%. When the concentrations of L-histidine and β-alanine methyl ester hydrochloride were 140 mM and 210 mM, respectively, the concentration of L-carnosine reached 105 mM by adding β-alanine methyl ester hydrochloride in batches, which increased the concentration of L-carnosine by 3.28 times compared with the nonbatch feeding. In conclusion, the ability of As DmpA to catalyze L-carnosine synthesis was improved by molecular modification technology and batch feeding methods, which provides an excellent method for the production of L-carnosine. [Display omitted] • An efficient enzyme for synthesizing L-carnosine was discovered and identified. • The catalytic efficiency of L341W is 1.37 times higher than that of WT. • Conversion of L-carnosine is more than 90%. • Batch feeding method increases the production rate by 3.28 times. [ABSTRACT FROM AUTHOR]

The natural pomelo peel fibers powders coating was obtained by spraying method, and this coating was underwater superoleophobic and could be applied in oil/water separation. The pre-wetted sample's separation efficiency was up to 97.0% for light or heavy oils/water mixture only in gravity-driven mass flow. And the pomelo peel powders coatings could still retain more than 98.0% separation efficiency water/soybean oil mixtures after 50 separation cycles. In this article, separation efficiency of natural pomelo peel powders coated mesh was over 97.0% in different pH water/soybean oil mixtures. All these features have shown that the natural and environment-friendly pomelo peel powders coating have enough potential applications in the field of oil/water separation. [ABSTRACT FROM AUTHOR]

Fumonisin B 1 (FB 1 ) is one kind of mycotoxins that has the neurotoxicity, carcinogenicity, hepatotoxicity and immunotoxicity produced by the fungus Fusarium verticillioides , which commonly infects corn and other crops and is harmful to animal and human health upon consumption of FB 1 -contaminated feed or food. However, the mechanism of immunotoxicity, especially the immunosuppression induced by FB 1 is still unclear. The most pivotal cells in the induction of immune responses are dendritic cells (DCs). In this study, we used murine bone marrow-derived dendritic cells (BMDCs) as a model system to elucidate the effect of FB 1 on the function of BMDCs through biological methods. We found that FB 1 reversed the morphological changes and enhanced the endocytosis of FITC-dextran in LPS-treated BMDCs. At the same time, FB 1 decreased the LPS-induced expressions of MHC II, C[1]D80 and CD86 molecules in BMDCs ( p < 0.05), as well as the T-cell stimulatory capacity of BMDCs ( p < 0.01). Moreover, the secretions of IL-6, IL-10 and IL-12, but not TNF-α induced by LPS exposure were suppressed by FB 1 in a dose dependent ( p < 0.01). It was considered that the immunosuppressive effects of FB 1 were mainly caused by changing the morphology and interfering with the process of antigen uptake, processing and presentation. The results highlighted that FB 1 had the capacity to modulate the immune responses of BMDCs. [ABSTRACT FROM AUTHOR]

The amorphous WO 3 coatings are prepared by a simple chemical deposition at room temperature. And the coatings modified with FAS-17 could obtain superamphiphobicity. The chemical composition, surface morphology, surface groups were respectively investigated with XRD, XPS, SEM, FT-IR and contact angles measurement. In order to study the particles’ size, the TEM pictures is applied. The wettability of the coatings were characterized by contact angles and surface adhesion abilities. Results show that the coatings were composed of amorphous micro-nano WO 3 at 60 °C, and those coatings could be easily fabricated and obtain superamphiphobicity. In meanwhile, the coatings possessed of low adhesion and high contact angles to water and oil. [ABSTRACT FROM AUTHOR]

We propose a new feature extraction method of liver pathological image based on multispatial mapping and statistical properties. For liver pathological images of Hematein Eosin staining, the image of R and B channels can reflect the sensitivity of liver pathological images better, while the entropy space and Local Binary Pattern (LBP) space can reflect the texture features of the image better. To obtain the more comprehensive information, we map liver pathological images to the entropy space, LBP space, R space, and B space. The traditional Higher Order Local Autocorrelation Coefficients (HLAC) cannot reflect the overall information of the image, so we propose an average correction HLAC feature. We calculate the statistical properties and the average gray value of pathological images and then update the current pixel value as the absolute value of the difference between the current pixel gray value and the average gray value, which can be more sensitive to the gray value changes of pathological images. Lastly the HLAC template is used to calculate the features of the updated image. The experiment results show that the improved features of the multispatial mapping have the better classification performance for the liver cancer. [ABSTRACT FROM AUTHOR]

Abstract Tungsten trioxide (WO 3) and titanium dioxide (TiO 2) decorated commercial stainless steel meshes (SSM 304) were fabricated by chemical deposition and dip coating. WO 3 and TiO 2 particles were firmly and uniformly coated on the membrane surfaces, forming rough micro-nano double structures with underwater superoleophobicity, large contact angles and low oil-adhesion characteristic. Furthermore, the as-prepared membranes achieved effective oil-in-water (O/W) emulsions separation with high efficiency up to 98.5% or more. The separation of O/W emulsions was easily implemented under gravity with water fluxes of >200 L m−2 h−1 or low pressure with water fluxes up to 1300 L m−2 h−1 or more. In addition, the superhydrophilic membranes with WO 3 /TiO 2 coatings were demonstrated for high oil rejection, stable underwater superoleophobic properties after abrasion treatment and steady water permeation flux after several cycles. Highlights • A Method to prepare WO 3 /TiO 2 decorated steel meshes is proposed. • Membranes have a solid structure, good stability and underwater superoleophobicity. • Effectively membrane separation of stabilized oil-in-water emulsions. • Composite membranes have outstanding recyclability and potential for oil/water separation. [ABSTRACT FROM AUTHOR]