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In this study, Saccharomyces cerevisiae and non-Saccharomyces strains were isolated from sourdough. S. cerevisiae SQJ20, which had a stronger gas-producing capacity than commercial activated dry yeast, was selected from 78 strains of S. cerevisiae. Wickerhamomyces anomalus GZJ2 and Torulaspora delbrueckii SDJ6 were selected to improve the quality of steamed bread. Co-fermentation with S. cerevisiae SQJ20 and W. anomalus GZJ2 at a ratio of 1:2 significantly improved the quality of steamed bread. Furthermore, W. anomalus GZJ2 increased the contents of total protein and free amino acid (13.69%), with the increase being greatest in the sweet amino acid proline (94.69%), the aromatic amino acid phenylalanine (82.63%), and the essential amino acid lysine (66.26%). The electronic nose and sensory evaluation results corroborated that the addition of W. anomalus GZJ2 improved the quality of steamed bread. In conclusion, co-fermentation with S. cerevisiae SQJ20 and W. anomalus GZJ2 could improve the quality of steamed bread without extending the fermentation time. Our observations provide a reference for the industrial production of flavored steamed bread.

Objective To cultivate glioblastoma U87 stem-like cells (SLCs) and to detect the level of stemness biomarkers, mitochondrial respiratory capacity and the capacity of in vivo tumorigenesis. Methods B-27, growth factors EGF and bFGF was added into DMEM/F-12 culture in serum-free stem cell culture medium for U87 SLCs. Suspended culture of U87 SLCs was suspended using the neuro-sphere formation assay, while adherent culture of U87 SLCs was achieved by coating Matrigel matrix on the culture surface. The mRNA and protein level of stemness biomarkers in culture were detected using real-time quantitative PCR and Western blot. The proportion of CD133+ cells in culture was detected by flow cytometry. The changes of cell oxygen consumption rate were detected by Seahorse cell metabolism analysis. Cell tumorigenesis ability was verified by subcutaneous tumor transplantation in animals. Results U87 SLCs in stem cell culture medium would grow into typical sphere morphology within one week, and the spheres would continue to grow as the culture process prolongs. At the appropriate concentration of adhesive, U87 SLCs adhered to and grow well in stem cell culture medium. The mRNA transcription of stemness biomarkers such as CD133, nestin, OLIG2, CD44, CD15, and integrin α6(ITGA6) was significantly increased as found in both culture methods, and the protein levels of CD133 and nestin were also increased under both methods(P＜0.05). U87 SLCs showed higher mitochondrial reserve respiratory capacity (P＜0.05). U87 SLCs could form larger subcutaneous tumors with fewer inoculated cells (P＜0.05), and grew faster in vivo with stronger tumorigenic ability. Conclusions U87 SLCs have typical stemness characteristics and may function as tumor cell model with higher stemness properties.

Aiming at improving the strength-plasticity match in the as-cast state of the most widely used Ti-6Al-4V the present work designs Ti-Al-V-Zr alloys on the basis of the dual-cluster formula of Ti-6Al-4V, α-{[Al-Ti12]（AlTi2）}12 +β-{[Al-Ti14]（V2Ti）}5： first, the alloys are more biased towards α-Ti by decreasing the number of β unit to 2, then, the stability of β-Ti is improved by increasing the number of V atoms in β unit to 3, and finally, Zr （x=1-5） replaces Ti in the β unit. Finally α-{[Al-Ti12]（AlTi2）}15-β-{[AlTi14-xZrx]V3）}2 is obtained, Ti-（6.64-6.82）Al-（2.42-2.35）V-（1.44-7.02）Zr （mass fraction,%） alloy is designed. The alloy ingots are prepared by melting in a non-consuming vacuum are furnace, and the alloy bars are suction-cast in copper mould. The results show that the alloys are all in α' martensite structure, showing morphologies changing from acicular Widmannstatten structure at lower Zr contents to net-basket structure at higher Zr contents. Among the designed alloys, Ti-6.64Al-2.35V-7.02Zr （x=5） with a net-basket structure, has the best mechanical properties： yield strength of 806 MPa, tensile strength of 963 MPa, and elongation of 5.9%, which are respectively 23%, 19% and 51% higher than those of Ti-6Al-4V alloy under the same preparation condition. In particular, the specific strength and specific hardness are 217kN•m/kg and 0.71 GPa•cm3/g, which are 18% and 10% higher than Ti-6Al-4V alloy.

[Objective] This study accurately quantified the degree of drought sensitivity of ecosystems to provide reference for early warning of ecological drought and reduction of ecological losses. [Method] The standardized ecological water deficit index (SEWDI) was constructed based on the ecological water deficit in Northwest China, and the ecological drought sensitivity was defined by combining water use efficiency (WUE) of vegetation. The Copula method was used to analyze the sensitivity of ecological drought by exploring the probability of WUE increase under the condition of increasing ecological drought. [Result] The ecological water deficit of vegetation in the Tarim Basin, Kunlun Mountains, Turpan Basin, Qaidam Basin and Hexi Corridor was high, with the highest monthly mean value of 75 mm. SEWDI was strongly correlated with WUE in most regions and areas with significantly positive correlation accounted for 24. 2% of the total region, mainly in Xinjiang, western Qinghai and southern Shaanxi. The areas with significantly negative correlation accounted for 36. 8% of the total region, mainly in the Loess Plateau. With the intensification of ecological drought, the sensitivity of WUE to ecological drought was not tnonotonically increased in different regions. The sensitivity of WUE to ecological drought increased with the increase of drought stress during the vegetation growth period, and the sensitivity of ecological drought in grassland was higher than that in forest land and cropland. The rate of increase in WUE probability from May to June was the fastest, and the monthly average rates of increase in WUE probability in the conditions of light drought-moderate drought, moderate drought-severe drought and severe drought-extreme drought were 0.09, 0.07, and 0.06, respectively. [Conclusion] WUE can well reflect the ecological drought sensitivity of vegetation under drought stress during the growing period and can be used as a factor to characterize ecological drought sensitivity. [ABSTRACT FROM AUTHOR]

In this work, lanthanum hydroxide nanocrystals (nano-La(OH)3) were firstly prepared using a hydrothermal method, whereas their microstructure was then characterized. Afterwards, coordination between the hydroxy groups of nano-La(OH)3 and the carboxyl groups in polyamic acid (PAA) was implemented, followed by spin-coating and thermal imidization to prepare nano-La (OH)3/polyimide (PI) composite ultra-thin films. The structure and performance of nano-La (OH)3/PI composite ultra-thin films were characterized. It was shown that the nano-La(OH)3/PI ultra-thin films were colorless and transparent with a thickness around 1.66 µm, and that the surface of the films was flat with a roughness of 5.85. Moreover, the nanocrystals were uniformly dispersed in the films. The dielectric constant of films was determined to be 4. 63, higher than that of pure P(-3.20). The ultra-thin films showed great potentials as solar panel backsheets, micro-memoria devices and smart skins. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to analyze the bacteria in dental caries and establish an optimized dental-ca-ries diagnosis model based on 16S ribosomal RNA (rRNA) data of oral flora., Methods: We searched the public databa-ses of microbiomes including NCBI, MG-RAST, EMBL-EBI, and QIITA and collected data involved in the relevant research on human oral microbiomes worldwide. The samples in the caries dataset (1 703) were compared with healthy ones (20 540) by using the microbial search engine (MSE) to obtain the microbiome novelty score (MNS) and construct a caries diagnosis model based on this index. Nonparametric multivariate ANOVA was used to analyze and compare the impact of different host factors on the oral flora MNS, and the model was optimized by controlling related factors. Finally, the effect of the model was evaluated by receiver operating characteristic (ROC) curve analysis., Results: 1) The oral microbiota distribution obviously differed among people with various oral-health statuses, and the species richness and species diversity index decreased. 2) ROC curve was used to evaluate the caries data set, and the area under ROC curve was AUC=0.67. 3) Among the five hosts' factors including caries status, country, age, decayed missing filled tooth (DMFT) indices, and sampling site displayed the strongest effect on MNS of samples ( P =0.001). 4) The AUC of the model was 0.87, 0.74, 0.74, and 0.75 in high caries, medium caries, low caries samples in Chinese children, and mixed dental plaque samples after controlling host factors, respectively., Conclusions: The model based on the analysis of 16S rRNA data of oral flora had good diagnostic efficiency.

Objectives: To evaluate the susceptibility of Streptococcus mutans (S. mutans) to NaF and the effects of Candida albicans (C. albicans) metabolites on the metabolic activity and drug resistance of S. mutans ., Methods: The minimum inhibitory concentration (MIC) and MIC based on metabolic activity (MIC-MA) of NaF against S. mutans were measured through the broth dilution test and D 2 O-labeled single-cell Raman microspectroscopy, respectively, to explore the inhibitory effect of NaF on the growth and metabolism of S. mutans . The effects of different concentrations of C. albicans supernatant on the metabolic activity of S. mutans were evaluated by using D 2 O-labeled single-cell Raman microspectroscopy. The correlation between C. albicans and S. mutans was explored throughassessing the drug resistance of S. mutans against NaF in a mixed system containing C. albicans supernatant by using D 2 O-labeled single-cell Raman microspectroscopy., Results: The MIC and MIC-MA of NaF against S. mutans were 0.4 g·L -1 and 1.2 g·L -1 , respectively. At the MIC level, S. mutans showed completely inhibited growth but retained high metabolic activity. Therefore, S. mutans may regain its virulence. At the MIC-MA level, the metabolic activity of S. mutans was inhibited only when the NaF concentration reached 3×MIC. At the concentration of OD 600 ≥0.5, the C. albicans supernatant significantly promoted the metabolic activity of S. mutans at different time points ( P <0.05). In the mixed system, the susceptibility of S. mutans to NaF decreased, and statistical differences at different time points were observed ( P <0.05). The metabolic activity of S. mutans was inhibited completely only at the concentration of 4×MIC (1.6 g·L -1 )., Conclusions: D 2 O-labeled single-cell Raman microspectroscopy is suitable for evaluating the effects of drugs on bacterial metabolic activity. In the mixed system, the metabolites in the C. albicans supernatant at the concentration of OD 600 ≥0.5 significantly promoted the metabolic activity of S. mutans and reducedthe susceptibility of S. mutans to NaF.

Objectives: To systematically evaluate the feasibility of D 2 O-labeled single-cell Raman micro-spectroscopy in drug resistance research and test the susceptibility of Enterococcus faecalis ( E. faecalis )to sodium hypochlorite., Methods: 1) The growth of E. faecalis in different doses of D 2 O and the regularity of D 2 O intake were evaluated through absorbance measurement and D 2 O-labeled single-cell Raman micro-spectroscopy to examine the universality of D 2 O-labeled single-cell Raman micro-spectroscopy in bacterial resistance research. 2) Broth dilution method and absorbance measurement were performed to determine the minimum inhibitory concentration (MIC) of NaClO against E. faecalis and the MIC based on metabolic activity (MIC-MA) in vitro via D 2 O-labeled single-cell raman micro-spectroscopy., Results: 1) The growth of E. faecalis was not significantly inhibited by ≤40% D 2 O in the medium. E. faecalis could actively metabolize D 2 O and exhibit a C-D ratio in specific areas of Raman micro-spectroscopy results. The C-D ratio of E. faecalis at the stationary phase was positively correlated with D 2 O concentration. 2) The MIC and MIC-MA of NaClO against E. faecalis were 0.45 and 0.9 g·L -1 , respectively. The concentration of MIC-MA was twice that of MIC., Conclusions: D 2 O-labeled single-cell Raman micro-spectroscopy is important in screening antimicrobial agents and evaluating the efficacy of antimicrobial agents. It is suitable for evaluating the effect of drugs on bacterial metabolic activities. NaClO showed an effective antimicrobial activity against E. faecalis . E. faecalis ceased propagation yet remained highly metabolically active when it was exposed to NaClO at the MIC level. The metabolic activity of most cells was inhibited only when they were exposed to NaClO at the MIC-MA level.

Sucrose is a natural product occurs widely in nature. In living organisms such as plants, sucrose phosphate synthase (SPS) is the key rate-limiting enzyme for sucrose synthesis. SPS catalyzes the synthesis of sucrose-6-phosphate, which is further hydrolyzed by sucrose phosphatase to form sucrose. Researches on SPS in recent decades have been focused on the determination of enzymatic activity of SPS, the identification of the inhibitors and activators of SPS, the covalent modification of SPS, the carbohydrate distribution in plants regulated by SPS, the mechanism for promoting plant growth by SPS, the sweetness of fruit controlled by SPS, and many others. A systematic review of these aspects as well as the crystal structure and catalytic mechanism of SPS are presented.