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Summary: Escherichia coli (E. coli) biofilm is the major cause of its high lethality in foodborne illness. Controlling E. coli biofilm formation is a critical way to reduce foodborne diseases. Here, chiral borneol isomers (L‐borneol, D‐borneol, and isoborneol) were identified as E. coli chemorepellents, which reduced reversible adhesion at the initial stage of biofilm formation. Borneols directly inhibited biofilm production and their inhibitory capacities were associated with the chiral stereochemical structures (L‐borneol > D‐borneol > isoborneol). A transcriptomic study revealed the inhibitory mechanism of borneols was attributed to the bacterial motility intention and motility energy system. The most effective isomer, L‐borneol, reduced bacterial energy metabolism and increased E. coli chemotaxis motility intention through the up‐regulation of genes associated with flagellar assembly and bacterial chemotaxis pathways. This work demonstrates that borneols are biofilm inhibitors and supports the potential of borneols as a stereochemical antimicrobial strategy to reduce foodborne pathogenic bacterial contamination. [ABSTRACT FROM AUTHOR]

Halide perovskites have attracted increasingly attention as "rising star" materials for advanced photonics and optoelectronics. Construction micro‐/nano‐architecture of perovskites will provide a good platform to investigate and optimize the fundamental photon–matter–structure interaction. It will also improve the properties, pixelate and miniaturize the integration of versatile optoelectronic devices for emerging applications. In this regard, femtosecond (fs) laser processing technique has been widely used to fabricate micro‐/nano‐architecture with high spatial resolution, limitless flexibility, and unrestricted three‐dimensional structuring capability at a large‐scale, low‐cost way. Concurrently, it is reported that the high refractive index, low thermal conductivity and ultrafast thermalization rate of perovskites are beneficial for the processing by fs laser into micro‐/nano‐architecture without the degradation of their optoelectronic properties. This review systematically summarizes the interaction of fs laser with perovskites, including the mechanisms, and phenomena. Besides the traditional optoelectronics and applications of halide perovskites, the novel properties and applications from optical structures generated by fs laser processing of perovskites are also discussed. The challenges and outlooks for fs laser processed perovskite materials and devices are highlighted. This review will promote the relevant fundamental research on light–matter–structure interaction, and facilitate the integration of perovskite micro‐/nano‐architecture‐based optoelectronic devices. [ABSTRACT FROM AUTHOR]

ABSTRACT Analyzing the spatial and temporal variations of offshore crude oil transportation at China's coastal ports is critical for the country's energy security. The automatic identification system provides high‐resolution real‐time data on China's offshore crude oil transportation, offering more precise spatial and temporal insights than existing statistical studies. In this study, we propose a novel method for calculating offshore crude oil transportation volumes by considering the operational status of crude oil tankers as “empty” or “full.” This approach enhances reliability and provides detailed port‐level transport data. Our findings reveal notable similarities between the centrality measures of maritime oil transportation and oil tanker networks, but significant differences in community divisions. Specifically, in the tanker networks, Chinese ports are categorized into three regions, with one region being dominant and the other two regions containing only four ports. In contrast, the oil flow networks show China divided into two major regions and two minor ones. This study offers valuable contributions to strengthening energy security in China and supports informed policy development and implementation. [ABSTRACT FROM AUTHOR]

A 3D mathematical model on the multiphase flow and splashing phenomenon in a 210 t Basic oxygen furnace converter is established. The turbulent multiphase flow of the molten steel, slag, and oxygen is simulated by the combined realizable k−ε model and volume of fluid model. The trajectory of argon bubbles and the interaction between the molten steel and argon is simulated by the two‐way coupled Lagrangian discrete phase model. Effects of the lance height and bottom‐blowing gas flow rate on the multiphase flow and splashing phenomenon are investigated. The results indicated that the cavity depth is decreased from 0.45 to 0.36 m when the lance height increases from 1700 to 2300 mm. The cavity depth is not significantly affected by the bottom‐blowing argon flow rate with the 44 000 m3 h−1 top‐blowing oxygen flow rate and 1700 mm lance height. The increased lance height resulted in a decrease in splashing. When the oxygen lance height increases from 1700 to 2300 mm, the amount of the splashed molten steel decreases from 3774.3 to 1953.0 kg. [ABSTRACT FROM AUTHOR]

A three‐dimensional mathematical model on fluid flow, ferrochrome dissolution, and mixing phenomena in a nitrogen‐stirred gas‐oxygen refining furnace is established. The multiphase fluid flow is simulated using the standard k–ε model, the volume of fluid (VOF) model, and the Lagrangian discrete phase model. Interfaces between fluids are tracked by the VOF model, and nitrogen bubbles are treated as discrete phase particles. The melt time of ferrochrome particles and the local mixing time are calculated using the user‐defined function. Effects of gas flow rate and bottom tuyere configuration on the fluid flow and the melting and mixing of ferrochrome are investigated. The results show that the average turbulent kinetic energy and its dissipation rate first increase and then decrease with the increasing gas flow rate, while the melting time and mixing time first decrease and then increase. The shortest melting and mixing time with the condition of seven bottom tuyeres are reached when the gas flow rate is 6.5 Nm3 min−1, which are 40.5 and 94.6 s, respectively. The mixing time decreases from 190.0 to 104.5 s when the three bottom tuyeres configuration changes to the seven bottom tuyeres configuration with the gas flow rate of 3.9 Nm3 min−1. [ABSTRACT FROM AUTHOR]

The current paper addresses the problem of stabilizing multiple aerial robots cooperatively transporting a cable‐suspended payload by an aeromechanic method. Instead of relying on global navigation satellite systems (GNSS) or vision and communication for agents to actively estimate and control the state of the multibody dynamics, lightweight air dampers to make the multiagent system inherently stable at its equilibrium state, permitting the robots to safely carry a load at a constant velocity are employed. This is achieved without additional state estimation or active correction. The proposed framework is proven stable and verified by simulations and extensive flight experiments. Lightweight mechanical dampers (under 7 g) are shown to be effective in attenuating undesired oscillations and overcoming disturbances. To this end, a team of four robots cooperatively transporting a payload over 20 m in open space is demonstrated, and three robots safely transporting a point‐mass payload over a distance of 45 m outdoors. The promising outcomes highlight the benefits of the passive strategy, which demands minimal hardware components and computation to realize the sophisticated aerial transport task. [ABSTRACT FROM AUTHOR]

Triboelectrification for contacts between three types of materials—metals, polymers, and semiconductors—are investigated. The results show that triboelectrification is a charge exchange process between the surfaces of two friction materials, and its output is the synergetic effects of the electrostatic induction (ESI) and dynamic junction modulation (DJM). There are four current/voltage peaks in output of triboelectrification: two of them are attributed to the ESI effect and determined by the surface state densities and electron affinity difference of the materials, while the other two are associated with the DJM effect and determined by the charging exchange between the surface states and the depletion region. However, metals and polymers have no‐modulation of depletion region due to their high conductivity and insulating nature, respectively, thus only two peaks induced by the ESI effect are observable no matter what types of metals and polymers are in pair for contacting. Semiconductors have a depletion region, there will be two more output current/voltage peaks induced by the junction modulation when a semiconductor is in contact with any type of materials. The observations reveal a universal triboelectrification mechanism for contacts between materials, and provide an intuitive guidance for the development of high‐performance triboelectric nanogenerators. [ABSTRACT FROM AUTHOR]

Chinese local pigs have abundant phenotypes as a result of different cultures and habits of Chinese populations, geographic constraints and the long history of pig domestication. A comprehensive investigation of local Chinese pigs will benefit biodiversity research and future breeding practices. However, their classification and demographic history are not yet clear. We studied 91 Chinese local pigs from 14 breeds and 15 Chinese wild boars to reveal the dispersal of Chinese pigs, genetic groups and the demographic history. Based on spatial feature analyses, we believe that the geographic landscape played an important role in the dispersal of local pigs. According to genetic studies, Chinese pigs are divided into three groups where each group appears to have a distinct background. The nucleotide diversity, observed heterozygosity, runs of homozygosity and inbreeding coefficient varied among the groups and widespread migration also existed between the groups. Furthermore, demographic models have been constructed to explain the evolutionary relationship between the groups using the approximate Bayesian computation approach. These suggested that Chinese local pigs are inherited from an extinct Sus scrofa population from ~22 000 years ago. Then, the three groups diverged from ancestors ~16 000, ~11 000 and ~8700 years ago respectively. This study advances our understanding of the genetic variation and demographic history of Chinese local pigs. [ABSTRACT FROM AUTHOR]

Hybridization is widespread in nature and is a valuable tool in domestic breeding. The DHB (DaHuaBai) pig in South China is the product of such a breeding strategy, resulting in increased body weight compared with other pigs in the surrounding area. We analyzed genomic data from 20 Chinese pig breeds and investigated the genomic architecture after breed formation of DHB. The breed showed inconsistency in genotype and body weight phenotype, in line with selection after hybridization. By quantifying introgression with a haplotype‐based approach, we proposed a two‐step introgression from large‐sized pigs into small‐sized pigs to produce DHB, consistent with the human migration events in Chinese history. Combining with gene prioritization and allele frequency analysis, we identify candidate genes that showed selection after introgression and that may affect body weight, such as IGF1R, SRC, and PCM1. Our research provides an example of a hybrid formation of domestic breeds along with human migration patterns. [ABSTRACT FROM AUTHOR]