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Abstract The effects of the gas phase surface discharge plasma system with a spray reactor on yeast in 12, 36, and 60°Brix apple juice were evaluated. Results indicated that the number of Zygosaccharomyces rouxii LB cells in 0.5 L of 12°Brix apple juice was reduced by 5.60 log 10 after discharge plasma treatment for 30 min. When the soluble solids content increased from 12 to 60°Brix, yeast inactivation was decreased by 2.55 log 10. After treatment, the pH level of the apple juice only slightly increased, and the titratable acidity and concentration of reducing sugars remained unchanged. The total color differences between the plasma-treated and untreated samples in 12, 36, and 60°Brix apple juice were 9.53, 7.97, and 3.86. Meanwhile, the concentrations of alcohols, esters, aldehydes, and ketones—the main components of volatile compounds showed no significant change (p < 0.05). Industrial relevance Inactivation of microorganisms using nonthermal plasma technology can reduce food costs and minimize changes in food products and is therefore an alternative to heat-based technology. The proposed research showed that the gas phase surface discharge plasma treatment with a spray reactor can effectively reduce Zygosaccharomyces rouxii in apple juice. In addition, the effect of plasma treatment on the color and volatile compounds of the apple juice were determined. This study provided a technical support for the application of plasma technology in apple juice processing. Highlights • Yeast cells were reduced by 3.05–5.60 log 10 after plasma treatment for 30 min. • Increased soluble solids content negatively affected yeast inactivation. • Plasma treatment did not affect titratable acidity and reducing sugar content. • The total color differences in samples were 3.86–9.53 after plasma treatment. • Plasma treatment did not change in volatile compounds, compared with the control. [ABSTRACT FROM AUTHOR]

[Display omitted] • Urchin-like TiO 2 /Ti 3 C 2 O x (MXene) photocatalysts have been successfully fabricated. • Surface -O terminated Ti 3 C 2 O x has a work function about 0.3 eV higher than that of TiO 2. • The photocatalytic H 2 evolution and LEV degradation of TiO 2 /Ti 3 C 2 O x are 9.7 and 6.7 folds higher than those of TiO 2 , respectively. • The photocatalytic reaction pathways were carefully investigated. • The photogenerated carriers were efficiently separated at the TiO 2 /Ti 3 C 2 O x interface. The surface groups of MXene act as a decisive role on the performance of MXene-based photocatalysts. In this work, TiO 2 nano-whiskers were grown in-situ on Ti 3 C 2 T x , through a hydrothermal and post-heat treatment process, meanwhile, the surface groups of Ti 3 C 2 T x were unified -O adsorption. The as-prepared urchin-like TiO 2 /Ti 3 C 2 O x composite have efficient activity for photocatalytic hydrogen evolution and degradation of levofloxacin (LEV). The optimized hydrogen evolution reaction (HER) performance reached 346.8 μmol g-1 h−1, and the apparent quantum yield at 313 nm was 7.67%. Its hydrogen production performance and degradation rate of LEV were 9.7 and 7.7 folds higher than those of pure TiO 2 , respectively. The -O terminated Ti 3 C 2 O x achieving a work function about 0.3 eV larger than TiO 2 , as both DFT calculation and UPS measurement depicted. Therefore, the photogenerated e-/h+ were separated at the TiO 2 /Ti 3 C 2 O x interface via Schottky junction, a large amount of e- was enriched on Ti 3 C 2 O x , which enabled the photocatalyst with remarkable charge separation and photocatalytic performance. Meanwhile, the reaction pathways of TiO 2 /Ti 3 C 2 O x photocatalytic HER and LEV degradation/mineralization were carefully investigated. This study underlines the significance of surface groups on photocatalysts composed of MXenes, and sheds light on the new approach to the rational design of high-efficiency MXene-based photocatalysts. [ABSTRACT FROM AUTHOR]

Methyl jasmonate (MeJA) plays important roles on growth, gene expression and metabolite accumulation in plants. In this study, the physiological and biochemical characteristics, transcriptome and metabolome profiles of Isatis indigotica Fort., responded to MeJA were explored. Under the treatment, the contents of dry matter, chlorophyll and carotenoids increased significantly, while the water content did not. And the contents of soluble protein, flavonoid and lignin were also raised significantly, but the soluble sugar decreased. Besides, the enzyme activities of phenylalanine ammonia lyase (PAL), lipoxygenase (LOX), polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) increased, showing certain resistance characteristics of this plant. Based on RNA-seq, 31,769 unigenes were functionally annotated, and 2725 differential expressed genes (DEGs) identified. Among them, 57 DEGs covered most of the catalytic steps in general biosynthesis pathways of jasmonic acid, glucosinolates and phenylpropanoid. Referring to the metabolomics analysis, 175 significant differential metabolites were detected by GC-MS, combined with LC-MS method. Moreover, 53 differential metabolites were identified by the multivariate statistical analysis, mainly enriched in 37 different metabolic pathways, with most differential metabolites found in phenylalanine metabolism pathway. The results provided the comprehensive analysis on growth, transcriptome and metabolite profiles responded to MeJA, and gave new insights into revealing and enriching the functions of MeJA, contributing to explore the key genes and their functions on growth and metabolite accumulation and regulation process in I. indigotica. • MeJA could improve the seedling growth and enhance the resistance of I. indigotica. • A total of 2725 genes differentially expressed in response to MeJA. • 175 metabolites differentially changed in response to MeJA. [ABSTRACT FROM AUTHOR]

Cold atmospheric plasma is a promising sterilization technology in the food industry. However, there are only a few studies on the process of inactivating microorganisms in liquids, and it is necessary to establish an efficient prediction model before widespread industrial application. In this study, the commercial software COMSOL was used to establish a gas phase surface discharge plasma reactor simulation model, and experiments were subsequently performed to validate the model. Results showed that increasing the initial concentration of yeast in water has a negative effect on the inactivation process. In contrast, yeast inactivation was not significantly affected by reactor diameter changes from 40 mm to 50 mm. The model showed good fit to the experimental data under various operating conditions, and the value of the parameter associated with the reaction coefficients provided insight into the process. This model can be used for process design and improvement of plasma-inactivated liquid foods. • A coupled gas-liquid mass transfer-inactivation model was developed and validated. • Different voltages were used to verify the prediction effect of the model. • The influence of initial concentration and reactor dimensions was predicted. [ABSTRACT FROM AUTHOR]

Abstract: ZnSe quantum dots (QDs) were synthesized by using a novel oleic acid-controlled hydrothermal route. The as-synthesized QDs were easily dispersed in nonpolar solvents to form highly stable homogenous solutions, on the basis of which their optical properties were systematically investigated. It was found that the QDs had multiple optical properties of both obvious optical nonlinearity with a frequency-doubled Nd:YAG laser (532 nm) used as inducing beam and a strong photoluminescence emission at ca. 458 nm, suggesting that they have potential applications in complex functional optical devices. [Copyright &y& Elsevier]

• Richness of the lower respiratory tract microbiome is diminished in patients with lung cancer. • Bradyrhizobium japonicum was only discovered in patients with lung cancer. • Acidovorax was a lineage found only in patients with pulmonary diseases. • A model based on age, pack year of smoking and 11 kinds of microbiota was created and validated. Current evidence suggests that microorganisms are associated with neoplastic diseases; however, the role of the airway microbiome in lung cancer remains unknown. To investigate the taxonomic profiles of the lower respiratory tract (LRT) microbiome in patients with lung cancer. BALF samples were collected in a discovery set comprising 150 individuals, including 91 patients with lung cancer, 29 patients with nonmalignant pulmonary diseases and 30 healthy subjects, and an independent validation set including 85 participants. The samples were assessed by metagenomics analysis. Random forest regression analysis was performed to select a diagnostic panel. In the discovery set, richness was reduced in lung cancer patients compared with that in healthy subjects, and the microbiome of patients with nonmalignant diseases resembled that of patients with lung cancer. Interestingly, Bradyrhizobium japonicum was only found in patients with lung cancer, whereas Acidovorax was found in patients with cancer and nonmalignant pulmonary diseases. A microbiota-related diagnostic model consisting of age, pack year of smoking and eleven types of bacteria was built, and the area under the curve (AUC) for discriminating the patients with cancer was 0.882 (95%CI: 0.807-0.957) in the training set and 0.796 (95%CI: 0.673-0.920) in the independent validation set. Our study demonstrates that the LRT microbiome richness is diminished in lung cancer patients compared with that in healthy subjects and that microbiota-specific biomarkers may be useful for diagnosing patients for whom lung biopsy is not feasible. [ABSTRACT FROM AUTHOR]

Abstract MgO Al 2 O 3 SiO 2 glass-ceramics were prepared by melting method. The effects of replacement of Na 2 O by Fe 2 O 3 on crystallization behavior and acid resistance of glass-ceramics were studied. The results showed that with Fe 2 O 3 addition, the crystallization peak around 860 °C increased firstly and then decreased, while the peak around 1120 °C showed opposite changes. The crystallization peak around 1000 °C shiftted to low temperatures. With heat treatment temperature increasing from 880 to 1200 °C, μ-cordierite, spinel, sapphirine and α-cordierite precipitated successively in the glass samples. Fe 2 O 3 had little effect on the type of crystal phases, but had a great influence on their crystallinity and precipitation temperature. After heat treatment at 1200 °C, the main crystalline phase changed from μ-cordierite to α-cordierite for the glass sample without Fe 2 O 3. The addition of Fe 2 O 3 promoted the crystallization of α-cordierite at low temperatures, especially for 1 mol% Fe 2 O 3 doped sample, α-cordierite obviously precipitated at 1100 °C. All the base glass samples had poor acid resistance, which was greatly improved by heat treatment. When honeycomb structure α-cordierite appeared as the main crystalline phase, acid resistance deteriorated rapidly. A small amount of Fe 2 O 3 addition reduced the acid resistance. With Fe 2 O 3 content increasing, the acid resistance gradually improved. Highlights • Fe 2 O 3 had little effect on type of crystals, but had a great effect on their crystallinity and precipitation temperature. • The addition of Fe 2 O 3 promoted the crystallization of α-cordierite at low temperatures. • All the base glass samples had poor acid resistance, which was greatly improved by heat treatment. • When honeycomb structure α-cordierite appeared as the main crystalline phase, acid resistance deteriorated rapidly. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports on the thermal-induced performance of hexagonal metastable In2O3 nanocrystals involving in phase transition and assembly, with particular emphasis on the assembly for the preparation of functional materials. For In2O3 nanocrystals, the metastable phase was found to be thermally unstable and transform to cubic phase when temperature was higher than 600°C, accompanied by assembly as well as evolution of optical properties, but the two polymorphs coexisted at the temperature ranging from 600 to 900°C, during which the content of product phase and crystal size gradually increased upon increasing temperature. The assembly of In2O3 nanocrystals can be developed to fabricate In2O3 functional materials, such as various ceramic materials, or even desired nano- or micro-structures, by using metastable In2O3 nanocrystals as precursors or building blocks. The electrical resistivity of In2O3 conductive film fabricated by a hot-pressing route was as low as 3.72×10−3 Ωcm, close to that of In2O3 single crystal, which is important for In2O3 that is always used as conductive materials. The findings should be of importance for both the wide applications of In2O3 in optical and electronic devices and theoretical investigations on crystal structures. [ABSTRACT FROM AUTHOR]

In this paper, the interface properties and interfacial interaction were calculated by the first principle method, and the growth of γ-Fe boundary was inhibited by La 2 O 3 so as to refine the austenite grain was also analyzed. The calculated results show that the two-dimensional lattice mismatch between γ-Fe(110) plane and La 2 O 3 (001) plane is 8.7%. Therefore, the nucleation interface between γ-Fe and La 2 O 3 is most likely γ-Fe(110)/La 2 O 3 (001). Meanwhile, there are three kinds of interface models, which are Fe–La-OT, Fe–La-OM and Fe–La-Bridge, respectively. The interface adhesion work of Fe–La-OT interface is smallest, which is −0.10 J/m2, while, that of Fe–La-OM interface is largest, which is −0.02 J/m2. The ideal interface adhesion work of the three interfaces is negative, which indicates that they cannot be existed stably. The three kinds of interfacial chemical bonds are composed of ionic bonds and metallic bonds. The chemical bond polarity of Fe–La-OT interface is the strongest, and the metallic property of Fe–La-OM interface and Fe–La-Bridge interface is stronger than that of Fe–La-OT one. In addition, most interfacial interaction forces of the three interface models are repulsive, which indicates that La 2 O 3 has a good inhibitory effect on the growth interface of γ-Fe. Therefore, La 2 O 3 can inhibit the growth of γ-Fe boundaries so as to refine the austenite grains. Image 1 • Work of adhesion and interfacial energy ofγ-Fe(110)/La 2 O 3 (001) interfaces were calculated. • Interfacial electronic structures between γ-Fe and La 2 O 3 were analyzed. • Interfacial bond characteristics were revealed by electron localization function and interface DOS. • The mechanism that the La 2 O 3 refine the austenite grain was analyzed. [ABSTRACT FROM AUTHOR]

The first principles method was used to calculate the interface stability, interfacial electronic structure and bond characteristics of γ-Fe/CeO 2 heterogeneous nucleation interface. Meanwhile, The formation mechanism of (100)_γ-Fe/(111)_CeO 2 heterogeneous nucleation interface was also revealed. The calculation results show that the two dimensional lattice mismatch between (100)_γ-Fe and (111)_CeO 2 is 4.9%, which indicates that (100)_γ-Fe and (111)_CeO 2 satisfy the crystallographic condition for the formation of effective heterogeneous nucleation interface. There are two kinds of interface models, named as O1-Fe and O2-Fe. The stability of O1-Fe interface is the best and its interfacial energy is the lowest, which is 3.07 J/m2. The ideal interfacial adhesive strength of O2-Fe interface is the largest, which is 10.98 J/m2. The bond characteristics of the two interfaces are both mixtures of covalent bonds and ionic bonds. It reveals that (100)_γ-Fe and (111)_CeO 2 can form effective heterogeneous nucleation interfaces and O1-Fe interface model forms preferably during the heterogeneous nucleation beginning process. When the formation conditions meet the requirement for both interface structures, the adhesive strength of the O2-Fe interface is higher. Therefore, CeO 2 can act as effective heterogeneous nucleation substrate of γ-Fe to refine the austenite grains. Image 1 • Two dimensional lattice mismatch between (100)_γ-Fe/(111)_CeO 2 is 4.9%. • O1-Fe interface has the best stability and O2-Fe interface has the largest ideal bonding strength. • Interfacial bond characteristics are mixture of covalent bonds and ionic ones. • (100)_γ-Fe/(111)_CeO 2 heterogeneous nucleation interface formed preferably as O1-Fe type. [ABSTRACT FROM AUTHOR]