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Tebuconazole (TEB), a prominent chiral triazole fungicide, has been extensively utilized for plant pathogen control globally. Despite experimental evidence of TEB metabolism in mammals, the enantioselectivity in the biotransformation of R- and S-TEB enantiomers by specific CYP450s remains elusive. In this work, integrated in silico simulations were employed to unveil the binding interactions and enantioselective metabolic fate of TEB enantiomers within human CYP1A2, 2B6, 2E1, and 3A4. Molecular dynamics (MD) simulations clearly delineated the binding specificity of R- and S-TEB to the four CYP450s, crucially determining their differences in metabolic activity and enantioselectivity. The primary driving force for robust ligand binding was identified as van der Waals interactions with CYP450s, particularly involving the hydrophobic residues. Mechanistic insights derived from quantum mechanics/molecular mechanics (QM/MM) calculations established C2-methyl hydroxylation as the predominant route of R-/S-TEB metabolism, while C6-hydroxylation and triazol epoxidation were deemed kinetically infeasible pathways. Specifically, the resulting hydroxy-R-TEB metabolite primarily originates from R-TEB biotransformation by 1A2, 2E1 and 3A4, whereas hydroxy-S-TEB is preferentially produced by 2B6. These findings significantly contribute to our comprehension of the binding specificity and enantioselective metabolic fate of chiral TEB by CYP450s, potentially informing further research on human health risk assessment associated with TEB exposure.

Abstract Mahogany species (family Meliaceae) are highly valued for their aesthetic and durable wood. Despite their economic and ecological importance, genomic resources for mahogany species are limited, hindering genetic improvement and conservation efforts. Here we perform chromosome-scale genome assemblies of two commercially important mahogany species: Swietenia macrophylla and Khaya senegalensis. By combining 10X sequencing and Hi-C data, we assemble high-quality genomes of 274.49 Mb (S. macrophylla) and 406.50 Mb (K. senegalensis), with scaffold N50 lengths of 8.51 Mb and 7.85 Mb, respectively. A total of 99.38% and 98.05% of the assembled sequences are anchored to 28 pseudo-chromosomes in S. macrophylla and K. senegalensis, respectively. We predict 34,129 and 31,908 protein-coding genes in S. macrophylla and K. senegalensis, respectively, of which 97.44% and 98.49% are functionally annotated. The chromosome-scale genome assemblies of these mahogany species could serve as a vital genetic resource, especially in understanding the properties of non-model woody plants. These high-quality genomes could support the development of molecular markers for breeding programs, conservation efforts, and the sustainable management of these valuable forest resources.

Abstract Wood is the most important natural and endlessly renewable source of energy. Despite the ecological and economic importance of wood, many aspects of its formation have not yet been investigated. We performed chromosome-scale genome assemblies of three timber trees (Ochroma pyramidale, Mesua ferrea, and Tectona grandis) which exhibit different wood properties such as wood density, hardness, growth rate, and fiber cell wall thickness. The combination of 10X, stLFR, Hi-Fi sequencing and HiC data led us to assemble high-quality genomes evident by scaffold N50 length of 55.97 Mb (O. pyramidale), 22.37 Mb (M. ferrea) and 14.55 Mb (T. grandis) with >97% BUSCO completeness of the assemblies. A total of 35774, 24027, and 44813 protein-coding genes were identified in M. ferrea, T. grandis and O. pyramidale, respectively. The data generated in this study is anticipated to serve as a valuable genetic resource and will promote comparative genomic analyses, and it is of practical importance in gaining a further understanding of the wood properties in non-model woody species.

Abstract Acorales is the sister lineage to all the other extant monocot plants. Genomic resource enhancement of this genus can help to reveal early monocot genomic architecture and evolution. Here, we assemble the genome of Acorus gramineus and reveal that it has ~45% fewer genes than the majority of monocots, although they have similar genome size. Phylogenetic analyses based on both chloroplast and nuclear genes consistently support that A. gramineus is the sister to the remaining monocots. In addition, we assemble a 2.2 Mb mitochondrial genome and observe many genes exhibit higher mutation rates than that of most angiosperms, which could be the reason leading to the controversies of nuclear genes- and mitochondrial genes-based phylogenetic trees existing in the literature. Further, Acorales did not experience tau (τ) whole-genome duplication, unlike majority of monocot clades, and no large-scale gene expansion is observed. Moreover, we identify gene contractions and expansions likely linking to plant architecture, stress resistance, light harvesting, and essential oil metabolism. These findings shed light on the evolution of early monocots and genomic footprints of wetland plant adaptations.

A draft genome assembly of Cremastra appendiculata (D. Don) Makino, a traditional Chinese medicine plant, identified genes responsible for plant colchicine biosynthesis.

Lime and fly ash modified expandable poly styrene (EPS) lightweight soil reinforced by polypropylene fiber (FELS) is a new type of lightweight subgrade material. In order to study the road performance and strength formation mechanism of this material, California Bearing Ratio Test (CBR) and Scanning Electron Microscopy (SEM) were performed on FELS with different EPS and fiber content. The results show that: (1) the CBR value of FELS decreases with the increase of EPS particle content. EPS particles can take on a part of the skeleton, and at the same time play the role of weight reduction and volume replacement. (2) The addition of fiber can improve the CBR value of FELS and bear part of the tensile stress and shear stress of soil under pressure. The reinforcement effect of 0.1% fiber is the best content. (3) With the increase of curing age, the CBR value of the sample increases continuously. The increase of curing age can make the internal ion exchange and hydration reaction of the structure more complete and enhance the shear resistance. The results of this study can provide a reference for the application of FELS in subgrade engineering.

With the large-scale development of wind turbines, large flexible blades bear heavier loads. In the actual rotating work of blades, the coupling of structural deformation and motion produces a dynamic stiffening effect and spin softening effect, which affects the dynamic characteristics of blades. In this study, the finite element method is used to model the NREL 5MW blade, and the dynamic stiffening and spin softening effects are investigated using the modal analysis. The influence of rotating effects on the blade’s natural frequency is revealed. It is concluded that the effect of dynamic stiffening is more significant than that of spin softening, and the comprehensive result of the two effects is not simply the superposition of them but presents obvious nonlinearity.

This study investigated the unconfined compressive strength change law of cement modified slurries (CMS) under different curing ages. We conducted unconfined compressive strength tests using slurry and cement as raw materials. The cement contents were 5%, 10%, 15%, 20%, and 25%. The curing ages were 7, 14, 28, 56, 90, 120, 150, and 180 d. A time effect model of CMS strength was established based on the measured UCS strength-curing age and the strength-cement content curves. The test results proved that the UCS of the CMS increased significantly with an increase in the curing age, and after 90 days, the UCS gradually increased to a fixed value. The time effect model better characterized the relationship between the UCS of the CMS and the curing age and the cement content, as the predicted value had a high correlation with the measured value. We conducted scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) tests to analyze the microstructure and chemical composition of the CMS. The microscopic test results demonstrated that the increase of cement content and curing age increased the amount of gelling substances in the CMS and made the overall structure more compact, thereby increasing its macro strength.

Using polypropylene (PP) fiber and cement to modify iron-ore tailing and applying it to road engineering is an effective way to reuse iron-ore tailing. The compressive properties and deformation characteristics of PP-fiber-and-cement-modified iron-ore tailing (FCIT) under traffic load were studied by the unconfined-compressive-strength (UCS) test and the dynamical-triaxial (DT) test. The test results indicated that the UCS and residual strength both increased with increasing PP-fiber content, and tensile and toughness properties were positively correlated with PP-fiber content. Moreover, the dynamic elastic modulus and damping of FCIT both showed a negative linear relationship with cycle time. It can be found from the test results that 0.75% was the best PP-fiber content to modify iron tailing sand in this work. Lastly, a prediction model was developed to describe the relationship between the cumulative plastic strain, PP-fiber content and cycle time, which can effectively capture the evolution law of the cumulative plastic strain with cycle time of FCITs at different PP-fiber contents.

Floating offshore wind turbines (FOWT) have attracted more and more attention in recent years. However, environmental loads on FOWTs have higher complexity than those on the traditional onshore or fixed-bottom offshore wind turbines. In addition to aerodynamic loads on turbine blades, hydrodynamic loads also act on the support platform. A review on the aerodynamic analysis of blades, hydrodynamic simulation of the supporting platform, and coupled aero- and hydro-dynamic study on FOWTs, is presented in this paper. At present, the primary coupling method is based on the combination of BEM theory and potential flow theory, which can simulate the performance of the FOWT system under normal operating conditions but has certain limitations in solving the complex problem of coupled FOWTs. The more accurate and reliable CFD method used in the research of coupling problems is still in its infancy. In the future, multidisciplinary theories should be used sufficiently to research the coupled dynamics of hydrodynamics and aerodynamics from a global perspective, which is significant for the design and large-scale utilization of FOWT.

Helping students gradually develop collective knowledge is critical but generally faces great challenges. Employing a quasi-experimental design, this study investigated the impacts and mechanisms of analytics-supported reflective assessment on the collective knowledge advancement of undergraduates. The experimental group (n = 55) engaged in Knowledge Building inquiries with facilitation through analytics-supported reflective assessment, while the comparison class (n = 38) pursued Knowledge Building inquiries facilitated by portfolio-supported reflective assessment. This study found that analytics-supported reflective assessment positively and significantly influenced undergraduates' collective knowledge advancement. Path analysis revealed the mechanisms of analytics-supported reflective assessment for supporting undergraduates' collective knowledge advancement--the undergraduates' metacognitive engagement and cognitive engagement influenced each other, further influencing their contribution to collective knowledge advancement and domain understanding. This study holds significant practical implications for fostering students' knowledge building, inquiry, and metacognition by designing technology-enhanced learning environments as collaborative and metacognitive tools. Additionally, the study offers insights into the processes and mechanisms of reflective assessment, contributing to an understanding of how it enhances students' development of higher-order skills.