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Objective: The aim of this study was to obtain vanillin converting microorganism by ferulic acid and optimize of fermentation conditions. Methods: The strains that can produce vanillin by ferulic acid which is screened form Daqu of Baijiu. The single factor experiment and orthogonal experiment were applied to optimize the fermentation conditions by shake flask fermentation. Results: The results showed that isolate B2-12 was identified as Bacillus subtilis and the high yield of vanillin was reached 34.5 mg/L under the conditions of liquid loading 44%, pH 10, 43 ℃ and shaking speed 160 r/min for 4 days fermentation. Conclusion: The strain B2-12 can produce vanillin by ferulic acid and it has the potential to apply in the production of milk-flavoring substance.

【Objectives】 Nitrogen loss from agricultural soils is an environmental concern worldwide and the purpose of this paper is to investigate the impact of the types of nitrogen fertilizers and planting methods on reducing nitrogen loss from surface runoff and ammonia volatilization from paddy field. 【Method】 The experiment was conducted in a field with the rice established either from machine transplanting (MTR) or direct drill (DSR). Added to these were four nitrogen fertilizations: conventional fertilization (FFP), slow-controlled fertilizer combined with urea (CRF) and seaweed polysaccharide nitrogen fertilizer (HTN), with no nitrogen application as control (CK). In each treatment, we measured nitrogen loss from the surface runoff and ammonia volatilization. 【Result】 Nitrogen lost from surface runoff was dominated by ammonium nitrogen (NH4+-N), with the loss from the drainage prior to the planting accounted for approximately 52% of the total nitrogen loss from the surface runoff. The impact of fertilizers on total nitrogen loss from the surface runoff was ranked in the order of FFP > HTN > CRF, the same as the loss rate and intensity of ammonia volatilization (AV) for both MTR and DSR. Compared with FFP, CRF and HTN each in combination with MTR reduced the AV loss during the whole growth season by 12.5% and 4.3% respectively, with their associated AV intensity reduced by 43.1% and 17.8% respectively; when combining each with DSR, they reduced AV loss rate by 23.2% and 12.2% respectively, with their associated AV intensity reduced by 53.3% and 26.8% respectively. Compared with FFP, CRF and HTN increased the yield by 9.31% and 4.70%, respectively, for rice planted using MRT, and 9.25% and 4.91%, respectively, for rice planted using DSR. 【Conclusion】 During the whole growth season, planting rice using DSR increased the AV flux, nitrogen loss rate and AV intensity than planting with MTR. The impact of fertilizers on nitrogen loss from the surface runoff was ranked in the order of FFP > HTN > CRF. When the amounts of all applied nutrients were the same, selecting an appropriate nitrogen fertilizer with a rational combination with basal fertilization and tillering-stage dressing can not only reduce nitrogen loss, but also improve nitrogen use efficiency and ultimate yield.

The fragmented remodeling of historic districts undermines the spirit of place. Understanding the intricate relationship between the neighborhood environment and the spirit of place is essential for sustainable urban development. Current research predominantly relies on case studies and the concept of place, which are subjective and lack specific analysis of how the neighborhood environment shapes the spirit of place. In this study, we examine Chuancheng Street in Handan City as a case study. Utilizing the eXtreme Gradient Boosting (XGBoost) model and multi-source data, combined with SHapley Additive exPlanation (SHAP) and Partial Dependence Plots (PDP), we analyze the non-linear and synergistic effects of the street environment on the spirit of place in historic districts. The findings reveal that (1) the proportion of enduring sociability (PES) on the street significantly shapes the spirit of place, with cultural space elements being less prioritized in perception; (2) PES, green vision index (GVI), Integration_800 m, and mixed land use (MLU) have pronounced non-linear impacts on the spirit of place, with strong threshold effects, and these factors also demonstrate a synergistic effect; (3) There are notable spatial variations in the spirit of place across different blocks, particularly influenced by the authenticity of cultural heritage. This study provides fundamental insights into the spirit of place in historic neighborhoods, enabling a better understanding of complex urban dynamics and informing future street regeneration from a place perspective. [ABSTRACT FROM AUTHOR]

Melanoma is the most lethal skin cancer that originates from epidermal melanocytes. Recently, long non-coding RNAs (lncRNAs) are emerging as critical regulators of cancer pathogenesis and potential therapeutic targets. However, the expression profile of lncRNAs and their role in melanoma progression have not been thoroughly investigated. Herein, we firstly obtained the expression profile of lncRNAs in primary melanomas using microarray analysis and unveiled the differentially-expressed lncRNAs compared with nevus. Subsequently, a series of bioinformatics analysis showed the great involvement of dysregulated lncRNAs in melanoma biology and immune response. Further, we identified lncRNA CD27-AS1-208 as a novel nuclear-localized factor with prominent facilitative role in melanoma cell proliferation, invasion and migration. Mechanistically, CD27-AS1-208 could directly interact with STAT3 and contribute to melanoma progression in a STAT3-dependent manner. Ultimately, the role of CD27-AS1-208 in melanoma progression in vivo was also investigated. Collectively, the present study offers us a new horizon to better understand the role of lncRNAs in melanoma pathogenesis and demonstrates that CD27-AS1-208 up-regulation contributes to melanoma progression by activating STAT3 pathway. Targeting CD27-AS1-208 in melanoma cells can be exploited as a potential therapeutic approach that needs forward validation in clinical trials in the future.

By numerically solving the time-dependent Schrödinger equation, we study high-order harmonic generation from the asymmetric diatomic molecule HeH2+ in a corotating two-color circularly polarized laser field. Our results reveal a strong correlation between the molecule orientation and the harmonic yield. The harmonics in the plateau region can achieve an intensity modulation of one to two orders of magnitude with the change in the orientation angle. Through the time-dependent evolution of ionized electron wave packets combined with the analysis of the transition dipole moment between the continuum and bound states, the modulation of the harmonic strength may be attributed to the difference in the recollision angle of ionized electron wave packets relative to the molecules. In addition, the harmonic ellipticity is also affected by the molecular orientation. Notably, we found that the harmonic with greater ellipticity and higher intensity can be obtained with an orientation angle of 147°. These findings open up new avenues for achieving enhanced efficiency, the near-circular polarization of harmonics, and precise control over harmonic polarization states. [ABSTRACT FROM AUTHOR]