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Mixed dimensional van der Waals heterostructure based on layered two-dimensional molybdenum disulfide (MoS2) interfaced to gallium nitride (GaN) has attracted tremendous attention due to its unique properties and application in novel electronic, optoelectronic, and quantum devices. However, developing facile synthesis methods and insights into the exciton dynamics for this system still remains a major challenge. Here, a simple and cost-effective method is demonstrated for large-scale synthesis of monolayer MoS2 on differently doped GaN substrates. A mixed aqueous solution of Na2MoO4 and NaOH is spin-coated on GaN and sulfurated in one step by chemical vapor deposition (CVD). High quality monolayer MoS2 nanosheets with side length over 400 μm and surface coverage ratio of more than 90 % are achieved on GaN. Furthermore, the PL intensity, excitonic transition ratios and ultrafast exciton dynamics of MoS2 are observed to be largely modulated by the doping type of GaN, owing to substrate-induced doping, which is proved by Raman, PL and transient absorption spectroscopy. Notably, p-GaN can attract electrons from monolayer MoS2 and weaken its intrinsic n-doping, thereby facilitating higher PL intensity as well as longer exciton lifetime, while n-GaN provides strong n-doping and generates opposite effect. This work hereby presents a pathway for large-scale synthesis of MoS2/GaN heterostructures and further understanding of their charge transfer properties and exciton dynamics, which should inspire their applications for optoelectronic devices.

This article reviews the influencing factors of intraoperative pressure injury and the progress of preventive nursing. This paper provides reference and guidance to reduce the incidence of intraoperative pressure injury, improve patient comfort, reduce medical costs, and ensure patient nursing safety. (本文就术中压力性损伤发生的影响因素及预防护理进展进行了综述, 以期为降低术中压力性损伤的发生率、提高患者舒适度、降低医疗费用、保障患者护理安全提供参考和指导。)

Swine pathogens have a long history of zoonotic transmission to humans, occasionally leading to sustained outbreaks or pandemics. Through a retrospective epidemiological study of swine populations in China, we describe novel lineages of porcine hemagglutinating encephalomyelitis virus (PHEV) complex coronaviruses (CoVs) that cause exclusively respiratory symptoms with no signs of the neurological symptoms typically associated with classical PHEV infection. Through large-scale epidemiological surveillance, we show that these novel lineages have circulated in at least eight provinces in southeastern China. Phylogenetic and recombination analyses of twenty-four genomes identified two major viral lineages causing respiratory symptoms with extensive recombination within them, between them, and between classical PHEV and the novel respiratory variant PHEV (rvPHEV) lineages. Divergence times among the sampled lineages in the PHEV virus complex date back to 1886-1958 (mean estimate 1928), with the two major rvPHEV lineages separating approximately 20 years later. Many rvPHEV viruses show amino acid substitutions at the carbohydrate-binding site of hemagglutinin esterase (HE) and/or have lost the cysteine required for HE dimerization. This resembles the early adaptation of human CoVs, where HE lost its hemagglutination ability to adapt to growth in the human respiratory tract. Our study represents the first report of the evolutionary history of rvPHEV circulating in swine and highlights the importance of characterizing CoV diversity and recombination in swine to identify pathogens with outbreak potential that could threaten swine farming.

With the transformation of the war pattern under the information conditions, the corresponding object of equipment support also changes from “equipment-oriented” to “warfare-oriented”, and the equipment implement the joint support. Based on the characteristics of the equipment support task under the system combat conditions, the Joint Equipment Support task assignment model with the shortest transition time is established, and a model algorithm based on genetic algorithm is proposed. The validity and accuracy of the model and the algorithm are verified by the example simulation.

We develop game‐theoretic models to study the sourcing strategies of the two competing manufacturers who face customer returns due to product design mismatch. The manufacturers have opportunities to reduce the likelihood of customer returns by putting efforts into improving product design. Each manufacturer has the option to outsource product design and production to an upstream supplier or keep product design and production internally. We show that the sourcing decisions of the two manufacturers depend on the level of relative return from design investment (determined by the cost of design efforts, degree of horizontal product differentiation, and expected costs related to returns). We identify the sourcing strategy equilibrium and show that the higher cost of design effort and/or the higher degree of horizontal product differentiation expand, while the higher costs related to returns shrink, the range in which symmetric outsourcing is an equilibrium. Furthermore, as compared to symmetric insourcing, symmetric outsourcing not only softens the price competition but may also increase design effort levels, and thus both manufacturers are better off from outsourcing. However, symmetric outsourcing may hurt both consumer surplus and social welfare. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: In recent years, there has been a shift towards using non‐fullerene electron acceptors in organic solar cells (OSCs) as a replacement for fullerene derivatives. This change requires polymer donors that possess compatible physical properties, such as absorption range, HOMO energy level, miscibility, and crystallinity. Moreover, the high cost and poor batch‐to‐batch reproducibility of polymer donors also hinder future large‐scale manufacturing. These emphasize the need to explore alternative types of polymer donors. The imide‐functionalized building units possess several key attributes that make their polymers highly promising for non‐fullerene OSCs. These attributes include ease of synthesis, strong electron‐withdrawing ability, rigid and co‐planar structure, and the ability to easily tune solubility through imide side chains. In this review, we summarized the synthetic routes of imide building units, and the structural evolution of imide‐functionalized polymer donors by focusing on the effects of polymer structure on their physical, optoelectronic, and photovoltaic properties. We hope that this mini‐review will serve as a catalyst for future research on imide‐functionalized polymers toward high‐performance, cost‐effective, and durable organic solar cells (OSCs). [ABSTRACT FROM AUTHOR]

The rapid development of narrow‐bandgap nonfullerene acceptors (NFAs) has boosted the efficiency of organic solar cells (OSCs) over 19 %. The new features of high‐performance NFAs, such as visible‐NIR light absorption, moderate the highest occupied molecular orbitals (HOMO), and high crystallinity, require polymer donors with matching physical properties. This emphasizes the importance of methods that can effectively tune the physical properties of polymers. Owning to very small atom size and strongest electronegativity, the fluorination has been proved the most efficient strategy to regulate the physical properties of polymer donors, including frontier energy level, absorption coefficient, dielectric constant, crystallinity and charge transport. Owing to the success of fluorination strategy, the vast majority of high‐performance polymer donors possess one or more fluorine atoms. In this review, the fluorination synthetic methods, the synthetic route of well‐known fluorinated building blocks, the fluorinated polymers which are categorized by the type of donor or acceptor units, and the relationships between the polymer structures, properties, and photovoltaic performances are comprehensively surveyed. We hope this review could provide the readers a deeper insight into fluorination strategy and lay a strong foundation for future innovation of fluorinated polymers. [ABSTRACT FROM AUTHOR]