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The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible for the fragrance and pharmacological properties of agarwood. O -Methyltransferases (OMTs) are necessary for the biosynthesis of methylated PECs, but there is little known about OMTs in Aquilaria sinensis. In this study, we identified 29 OMT genes from the A. sinensis genome. Expression analysis showed they were differentially expressed in different tissues and responded to drill wounding. Comprehensive analysis of the gene expression and methylated PEC content revealed that AsOMT2 , AsOMT8 , AsOMT11 , AsOMT16 , and AsOMT28 could potentially be involved in methylated PECs biosynthesis. In vitro enzyme assays and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 6-methoxy-2-(2-phenylethyl)chromone. A transient overexpression experiment in the variety 'Qi-Nan' revealed that AsOMT11 and AsOMT16 could significantly promote the accumulation of three major methylated PECs. Our results provide candidate genes for the mass production of methylated PECs using synthetic biology. [ABSTRACT FROM AUTHOR]

We present a new magnetohydrodynamic-particle-in-cell (MHD-PIC) code integrated into the athena++ framework. It treats energetic particles as in conventional PIC codes, while the rest of thermal plasmas are treated as background fluid described by MHD, thus primarily targeting at multiscale astrophysical problems involving the kinetic physics of the cosmic rays (CRs). The code is optimized towards efficient vectorization in interpolation and particle deposits, with excellent parallel scaling. The code is also compatible with static/adaptive mesh refinement, with dynamic load balancing to further enhance multiscale simulations. In addition, we have implemented a compressing/expanding box framework that allows adiabatic driving of CR pressure anisotropy, as well as the δ f method that can dramatically reduce Poisson noise in problems where distribution function f is only expected to slightly deviate from the background. The code performance is demonstrated over a series of benchmark test problems, including particle acceleration in non-relativistic parallel shocks. In particular, we reproduce the linear growth of the CR gyro-resonant (streaming and pressure anisotropy) instabilities, under both the periodic and expanding/compressing box settings. We anticipate the code to open up the avenue for a wide range of astrophysical and plasma physics applications. [ABSTRACT FROM AUTHOR]

This paper studies alternative procurement modes for emergency supplies in the presence of a public sector and a private supplier. A key feature of such a supply chain is that the private supplier must consider commercial demand in addition to disaster demand. Three procurement modes are analysed: an option mode (OM), an order-before-disaster mode (OBDM) and a procurement-after-disaster mode (PADM). We provide the optimal decisions associated with these three modes. Theoretical results in the OM show that a large order is not always better for the private supplier. From theoretical and numerical comparative analyses, no mode is absolutely superior. For the public sector, there are two thresholds. When the disaster probability is less than the low threshold, the revenues of all procurement modes are the same; when the disaster probability is larger than the high threshold, the OBDM has the highest revenue; otherwise, the OM has the highest revenue. However, for the private supplier, the PADM always has the highest revenue. [ABSTRACT FROM AUTHOR]

Development of ovarian cancer involves the co-evolution of neoplastic cells together with the adjacent microenvironment. Steps of malignant progression including primary tumor outgrowth, therapeutic resistance, and distant metastasis are not determined solely by genetic alterations in ovarian cancer cells, but considerably shaped by the fitness advantage conferred by benign components in the ovarian stroma. As the dynamic cancer topography varies drastically during disease progression, heterologous cell types within the tumor microenvironment (TME) can actively determine the pathological track of ovarian cancer. Resembling many other solid tumor types, ovarian malignancy is nurtured by a TME whose dark side may have been overlooked, rather than overestimated. Further, harnessing breakthrough and targeting cures in human ovarian cancer requires insightful understanding of the merits and drawbacks of current treatment modalities, which mainly target transformed cells. Thus, designing novel and precise strategies that both eliminate cancer cells and manipulate the TME is increasingly recognized as a rational avenue to improve therapeutic outcome and prevent disease deterioration of ovarian cancer patients. [ABSTRACT FROM AUTHOR]