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Cytochrome P450s (CYPs) play crucial roles in regulating plant growth, development, and stress tolerance. In this study, a perennial ryegrass (Lolium perenne) CYP gene, LpCYP72A15, was identified as a candidate gene regulating plant osmotic stress tolerance based on a cDNA library screening in the background of yeast ∆hog1 mutant. LpCYP72A15 is localized in the plastids, and its expression was regulated by osmotic stress and ABA treatment. Overexpressing LpCYP72A15 significantly enhanced plant drought tolerance in both Arabidopsis and perennial ryegrass. Under drought stress, the transgenic ryegrass showed significant lower reactive oxygen species (ROS) levels, higher ROS‐scavenging enzymatic activities, and higher soluble sugar contents than the wildtype plants. Transient over‐expressing the gene also enhanced survival rates of ryegrass mesophyll protoplasts under H2O2‐induced oxidative or mannitol‐enforced osmotic stresses. Taken together, LpCYP72A15 confers oxidative‐ and osmotic‐stress tolerances that positively regulates plant drought tolerance in perennial ryegrass. [ABSTRACT FROM AUTHOR]

Dark excitons are fascinating for condensed matter physics, quantum information processing, and optoelectronics due to their long lifetimes. However, direct optical access to dark excitons is still challenging due to the violation of the spin selection rule. Here, a new scheme for the brightening of spin‐forbidden dark exciton in WS2 monolayers by creating artificial out‐of‐plane shear strain that induces an effective in‐plane pseudo‐magnetic field is proposed. To reveal dark excitons, low‐temperature magneto‐photoluminescence experiments on the strained WS2 monolayers are performed. It is found that the dark excitons appear at 59 meV below the bright ones and exhibit an asymmetric magnetic field dependence, which is in agreement with the model taking into account the effect of the out‐of‐plane shear strain on spin‐flip processes of exciton states. The fieldless scheme has great potential in the application of dark excitons for new quantum information processing devices. [ABSTRACT FROM AUTHOR]

Considering information security insurance, this paper investigates an information security investment game between two firms with complementary information assets. Each firm's information security investment and expected profit in Nash equilibrium (i.e., firms make decisions individually) and social optimum (i.e., firms make decisions jointly) are analyzed through rigorous theoretical analyses and numerical examples. We find that making decisions jointly will make the two firms as a whole obtain more profits than when they make decisions alone, whereas this does not mean that each firm will benefit from the joint decision‐making process. Our results show that a firm yields a smaller expected profit in the joint decision game than the individual decision game under some conditions. In addition, the impacts of a higher insurance price and a higher investment efficiency on a firm's information security investment and expected profit are explored. The results indicate that, for a single firm, a higher insurance price does not necessarily result in smaller profit, and a higher investment efficiency does not always lead to larger profit. Then we design a compensation‐based contract to coordinate the two firms' information security investments when they make decisions individually. The contract will make the two firms achieve social optimum and ensure that each firm yields more profits than firms without the contract. Finally, we extend our research by setting the insurance amount as a decision variable to verify the above analyses. [ABSTRACT FROM AUTHOR]

Understanding hot carrier dynamics between plasmonic nanomaterials and its adsorbate is of great importance for plasmon‐enhanced photoelectronic processes such as photocatalysis, optical sensing and spectroscopic analysis. However, it is often challenging to identify specific dominant mechanisms for a given process because of the complex pathways and ultrafast interactive dynamics of the photoelectrons. Here, using CO2 reduction as an example, the underlying mechanisms of plasmon‐driven catalysis at the single‐molecule level using time‐dependent density functional theory calculations is clearly probed. The CO2 molecule adsorbed on two typical nanoclusters, Ag20 and Ag147, is photoreduced by optically excited plasmon, accompanied by the excitation of asymmetric stretching and bending modes of CO2. A nonlinear relationship has been identified between laser intensity and reaction rate, demonstrating a synergic interplay and transition from indirect hot‐electron transfer to direct charge transfer, enacted by strong localized surface plasmons. These findings offer new insights for CO2 photoreduction and for the design of effective pathways toward highly efficient plasmon‐mediated photocatalysis. [ABSTRACT FROM AUTHOR]

We considered a general price‐setting newsvendor model in which the firm needs to make joint inventory and pricing decisions for short life‐cycle products before the selling season. The firm's production is subject to random yield and the retailer faces uncertain demand. There exists a secondary market for the firm to acquire or dispose of products. We study the effects of yield randomness on optimal decisions and the expected profit in the cost structure, on the condition that the unit prices of the secondary emergency purchase and sale are random functions of the yield. Using the theory of stochastic comparisons, our key findings are as follows. (a) When the unit price of secondary emergency purchase is nonincreasing with the yield realization, a stochastically larger yield rate leads to a higher expected profit for both supply cases. Moreover, for the multiplicative supply case, a stochastically larger yield rate results in a lower optimal sale price, but this is not true in the additive supply case. Numerical examples show that the effect of the yield rate on the optimal order quantity is uncertain for two supply cases. (b) When the unit price of secondary emergency purchase is nonincreasing convexly with the yield realization, a less variable yield rate leads to a higher expected profit for both supply cases. Numerical examples illustrate that the effects of the yield rate on the optimal sale price and the optimal order quantity are also uncertain. (c) Based on graphical comparisons, we find that the effect of yield randomness has a more significant impact on supply chain performance with a yield‐dependent secondary market price than that with a constant secondary market price. [ABSTRACT FROM AUTHOR]