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With the development of highway tunnels, the increasing number of continuous tunnels has brought forth a growing concern regarding the dispersion of pollutants between tunnel entrances. This study employs numerical simulations with Star CCM+ to analyze factors influencing pollutant dispersion between continuous tunnel entrances, such as inlet and outlet velocities, longitudinal spacing, and lateral wind. Results indicate that maintaining a constant longitudinal size ratio while increasing velocity ratio augments intrusion ratio. Altering longitudinal spacing and equivalent diameter does not affect dispersion with constant velocity and size ratios. The intrusion ratio decreases with increasing longitudinal size ratio at a constant velocity ratio. Increased lateral wind weakens intrusion with constant velocities and longitudinal size ratio. This investigation aims to identify ventilation measures for mitigating pollutant dispersion impact in continuous tunnels.

SUMMARY: Acteoside is a bioactive phenylethanoid glycoside widely distributed throughout the plant kingdom. Because of its two catechol moieties, acteoside displays a variety of beneficial activities. The biosynthetic pathway of acteoside has been largely elucidated, but the assembly logic of two catechol moieties in acteoside remains unclear. Here, we identified a novel polyphenol oxidase OfPPO2 from Osmanthus fragrans, which could hydroxylate various monophenolic substrates, including tyrosine, tyrosol, tyramine, 4‐hydroxyphenylacetaldehyde, salidroside, and osmanthuside A, leading to the formation of corresponding catechol‐containing intermediates for acteoside biosynthesis. OfPPO2 could also convert osmanthuside B into acteoside, creating catechol moieties directly via post‐modification of the acteoside skeleton. The reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR) analysis and subcellular localization assay further support the involvement of OfPPO2 in acteoside biosynthesis in planta. These findings suggest that the biosynthesis of acteoside in O. fragrans may follow "parallel routes" rather than the conventionally considered linear route. In support of this hypothesis, the glycosyltransferase OfUGT and the acyltransferase OfAT could direct the flux of diphenolic intermediates generated by OfPPO2 into acteoside. Significantly, OfPPO2 and its orthologs constitute a functionally conserved enzyme family that evolved independently from other known biosynthetic enzymes of acteoside, implying that the substrate promiscuity of this PPO family may offer acteoside‐producing plants alternative ways to synthesize acteoside. Overall, this work expands our understanding of parallel pathways plants may employ to efficiently synthesize acteoside, a strategy that may contribute to plants' adaptation to environmental challenges. [ABSTRACT FROM AUTHOR]

In the network function virtualization environment, aiming at the load imbalance of network, a topology and resource-aware virtual network function migration method (TRA-VNFM) is proposed. Firstly, according to the computing, storage and forwarding resource occupancy of the underlying network, the two-level dynamic threshold is set to classify the overload degree of physical nodes, and at the same time, the corresponding migration judgment conditions are formulated and the set of destination nodes to be migrated is calculated. Among them, high-overload nodes have priority to implement migration and have lower migration success conditions. Secondly, for the virtual network function deployed on the overload node, the resource-aware algorithm is used to set its migration weight.The more overload resources the virtual network function occupies, the larger its migration weight, combining the migration weight and resource demand to select the virtual network function to be migrated. Finally, the topology-aware algorithm of extreme value interaction is used to evaluate the nodes in the migration destination node set, taking the node with the highest evaluation as the migration destination node by considering all kinds of resource occupancy, processing delay and topological properties. Simulation experiments show that compared with the previous virtual network function migration methods, this method not only reduces the migration time, but also has better performance in the average delay of the service function chain, the revenue to expense ratio of network and the degree of load balancing.

Photosensitive micellar solutions of mixed surfactants and photosensitive additives have gained much interest. However, there are no reports on photosensitive micellar solutions containing trimeric cationic surfactant. In the study, novel photosensitive viscoelastic micellar solutions consisting of trimeric cationic surfactant (TEC) and trans‐ortho‐methoxycinnamic acid (trans‐OMCA) were investigated. This study utilized rheology, UV–vis spectroscopy, and cryo‐TEM to investigate the photo‐responsive behavior and mechanism of the TEC/trans‐OMCA micellar solutions. Rheological studies revealed that the concentration of TEC and trans‐OMCA, as well as temperature, significantly affected the viscoelastic properties of the micellar solutions. Furthermore, the Carreau and Maxwell models might be used to characterize the flow curves and viscoelasticity of the micellar solutions, respectively. Notably, TEC/trans‐OMCA micellar solutions exhibited excellent light‐induced thinning characteristic, with the optimal performance at a mass ratio of φ = 0.5. After UV irradiation, the zero‐shear viscosity of TEC/trans‐OMCA (0.6/0.3 wt%) micellar solution was reduced by 352 times, while the viscoelasticity and the area of hysteresis loops were significantly reduced. This drastic change in the rheological characteristics of the micellar solutions could be attributed to the photoisomerization of trans‐OMCA and the resulting changes in the internal microstructure of the solutions. Moreover, the viscosity of the micellar solutions diminished as the temperature increased, with the remaining viscosity of the TEC/trans‐OMCA (1.0/0.5 wt%) micellar solution at 36.4 mPa s at 95°C. This study expands on the potential utilization of oligomeric surfactants in the construction of photorheological viscoelastic fluids. [ABSTRACT FROM AUTHOR]

Studies on the spatiotemporal dynamics in ecosystem carbon and water exchanges are essential in predicting the effects of climate change on regional carbon and energy budgets. Using the eddy covariance technique, carbon and water fluxes were observed in a typical winter wheat ecosystem (WWE) and an agroforest ecosystem (AFE) in the southern Loess Plateau from 2004 to 2010. The seasonal and inter-annual variability in gross primary productivity (GPP), net ecosystem exchange (NEE), evapotranspiration (ET), and water use efficiency (WUE) were examined and the main influencing factors were identified using the Pearson correlation. The results indicate that the seasonal GPP and NEE showed a bimodal distribution in WWE, while this was unimodal in AFE. The sinusoidal function did well in the characterization of seasonal ET dynamics for both ecosystems, with the determination coefficients being 0.85 and 0.94, respectively. In WWE and AFE, the annual mean GPP were 724.33 and 723.08 g C m−2 a−1, respectively, and the corresponding ET were 392.22 and 410.02 mm a−1. However, the difference in NEE between the two ecosystems was obvious, NEE were −446.28 and −549.08 g C m−2 a−1, respectively, showing a stronger carbon sink in AFE. There were strong coupling relationships between the GPP and ET of both ecosystems; the overall slopes were 1.71 and 1.69, respectively. The seasonal trend of WUE was bimodal in WWE, with peak values of 3.94 and 3.65 g C kg−1 H2O, occurring in November and April, respectively. However, the monthly WUE in AFE had one single peak of 4.07 g C kg−1 H2O in January. Photosynthetically active radiation (PAR) and soil temperature (Ts) were most positively correlated with GPP, net radiation (Rn) and Ts were the major factors influencing ET, while vapor pressure deficit (VPD) and soil water content (SWC) were the major influencing factors for WUE. These results provide observational support for regional carbon neutrality simulations. [ABSTRACT FROM AUTHOR]

The Chinese Loess Plateau has undergone extensive revegetation to restore degraded land and enhance carbon sequestration. However, soil organic carbon (SOC) sequestrated in the soil profiles of deep-rooted plants has not been fully studied. Here, we investigated the SOC within a 0–23 m profile in farmlands and apple orchards converted from farmlands with different ages (A5, <5 years; A10, ~10 years; A15, ~15 years; A20, >20 years) and the controlling factors on three loess tablelands (Changwu, Qingyang, and Luochuan). The results show that SOC stocks among farmlands and orchards showed no significant difference (p = 0.88); however, SOC stocks showed a trend with tree ages, i.e., a decrease for A5 and A10 but an increase for A15 and A20. For the vertical variability, the SOC stock was the highest within 0–1 m, regardless of the standing age; however, the SOC stock in this layer only accounted for 8.8% of the total SOC stock (97.93 ± 9.18 kg m−2). Climate accounted for 82% of the variations and controlled the changes in SOC in the 0–1 m range, while soil texture dominated the SOC in the soil below 1 m, accounting for 57% of the SOC variations. The variations in SOC in the thick, unsaturated zones provide implications for future land use management and the sustainability of apple orchards in arid regions. [ABSTRACT FROM AUTHOR]

[Objective] To investigate the spatial distribution and cooperative utilization characteristics of soil water under the orchard-farmland mosaic pattern in the southern Loess Tableland. [Methods] The 10-year-old, 21-year-old, and 25-year-old apple orchards (AO10, AO21, and AO25) and their adjacent farmland were selected in Changwu tableland were selected to quantitatively calculate the contribution of soil water storage to water consumption of orchard. By measuring the soil water content at relevant sites in the orchard-farmland interface zone after the rainy season in 2021. [Results] The precipitation in 2021 is 756 mm, which was a typical wet year. The rainfall infiltration depth of farmland and AO21, AO25 orchards reached 8.4, 7.0, and 5.0 m at the end of November, respectively. AO10 orchard-farmland boundary zone is 4 m deep, the oil water content in the lower part is larger than that in the upper part, and the average soil water content was 25.5% in the 4-10 m soil layer. In AO21 orchard, the average soil water content of the 0-7 m soil layer was 22.1 %, and that of the 7-10 m soil layer was 15.0%. the average soil water content of the 0-5 m oil layer of AO25 orchard was 20.9%, and that of 5-10 m was 13.6%. The soil dry layer of AO21 and AO25 orchard was below 7.0 and 5.0 m, respectively. In the horizontal direction, the distance of soil water used by AO21 and AO25 orchards from adjacent farmland reached 5 and 8 m, respectively, and the water supply from fields to orchards at the agro-fruit interface was 0.08 and 0.25 m³/m² when the soil profile was divided by the upper boundary of the dry layer. Below is the actual water supply, which is 0.45 and 0.81 m³/m², respectively. [Conclusion] The mosaic layout of apple orchards and farmland in the Loess tableland region is a reasonable utilization structure, and factors such as the age of apple trees and the width of adjacent farmland should be considered in land planning and management. The research results will contribute to promote the sustainable utilization and spatial optimization of regional soil water resources. [ABSTRACT FROM AUTHOR]

In order to obtain the quality information of Taishan black tea and provide data support for the establishment of assessment criteria for quality control of Taishan black tea, in this study, 45 samples of Taishan black tea were collected during the summer to investigate their quality characteristics. The results showed that the Taishan black tea typically exhibited a dark-brown, curly appearance and a uniform texture. The tea soup displayed a bright orange-red color. The tea was mainly described as having a fruity aroma, followed by a caramel flavor, sweet aroma, flowery flavor, and clean aroma, with a strong and enduring fragrance. The taste profile was mostly heavy and mellow or heavy and strong, with fewer samples exhibiting slight bitterness and astringency. The tea leaves were characterized by a reddish-auburn color, a soft texture, and an even appearance. The main biochemical components of the Taishan black tea fell within the following ranges: water extracts (38.65–43.35%), free amino acids (1.41–3.45%), tea polyphenols (9.80–15.05%), catechins (6.11–9.03%), and caffeine (1.65–3.05%). The phenolic acid/amino acid ratio was 2.31–6.65%. Catechins and tea polyphenols emerged as critical indicators influencing taste quality, followed by amino acids, water extracts, and caffeine. The aroma analysis identified common compounds, such as 3-methyl-butanal, 2-methyl-butanal, decanal, 2-methyl-propanal, 1-octen-3-ol, and β-ionone, in most samples. These compounds exhibited relatively high contents and high odor activity values, making them the primary contributors to the tea's aroma. This investigation into the quality of Taishan black tea offers valuable scientific insights, providing a foundation for the standardization of Taishan black tea's quality. [ABSTRACT FROM AUTHOR]

Two novel UV photosensitive micellar systems, trimeric dodecyl anionic–cationic surfactant (TDCC)/trans-OMCA, and trimeric cetyl anionic–cationic surfactant (TCCC)/trans-OMCA, were successfully synthesized by using two different carbon chain length trimeric anionic–cationic surfactants (TACS, including TDCC and TCCC) and the photosensitive additive trans-o-methoxycinnamic acid (trans-OMCA). The incorporation of trans-OMCA resulted in a peak in the zero shear viscosity (η0) of the system at pH = 6.17–6.61. The flow behaviour of the TACS/OMCA system was well described by the Carreau-Yasuda model. Prior to UV irradiation, the TCCC/trans-OMCA system exhibited pronounced shear thinning, thixotropic, and viscoelastic properties. After UV irradiation at 365 nm, the isomerization of trans-OMCA to cis-OMCA caused the disruption of the network structures, leading to a significant decrease in the thixotropic and viscoelastic properties, resulting in a decrease in viscosity. The viscosity reduction rate of the TCCC/trans-OMCA system reached 99 %. The influence of the hydrophobic carbon chain length on the UV responsiveness was also investigated. The TDCC/trans-OMCA system exhibited an 86 % decrease in η0 after UV irradiation, highlighting the favorable effect of longer hydrophobic tail chains in improving the UV responsiveness of the micellar system. The UV light kinetics of the TCCC/trans-OMCA solution were studied and a rheological model was developed to accurately describe the viscosity changes. The TCCC was found to predominantly exhibit cationic characteristics at pH = 6.17–6.61. In this pH range, the 2 wt% TCCC/0.12 wt% NaSal system exhibited excellent viscoelasticity, and the addition of trans-OMCA disrupted the network structure resulting in a decrease in viscosity. After UV irradiation, the viscosity of the system increased by 2.5 times, confirming the potential of the TCCC/NaSal/trans-OMCA micellar system as a UV thickener. [ABSTRACT FROM AUTHOR]