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SUMMARY: The plant cuticle is composed of cuticular wax and cutin polymers and plays an essential role in plant tolerance to diverse abiotic and biotic stresses. Several stresses, including water deficit and salinity, regulate the synthesis of cuticular wax and cutin monomers. However, the effect of wounding on wax and cutin monomer production and the associated molecular mechanisms remain unclear. In this study, we determined that the accumulation of wax and cutin monomers in Arabidopsis leaves is positively regulated by wounding primarily through the jasmonic acid (JA) signaling pathway. Moreover, we observed that a wound‐ and JA‐responsive gene (CYP96A4) encoding an ER‐localized cytochrome P450 enzyme was highly expressed in leaves. Further analyses indicated that wound‐induced wax and cutin monomer production was severely inhibited in the cyp96a4 mutant. Furthermore, CYP96A4 interacted with CER1 and CER3, the core enzymes in the alkane‐forming pathway associated with wax biosynthesis, and modulated CER3 activity to influence aldehyde production in wax synthesis. In addition, transcripts of MYC2 and JAZ1, key genes in JA signaling pathway, were significantly reduced in cyp96a4 mutant. Collectively, these findings demonstrate that CYP96A4 functions as a cofactor of the alkane synthesis complex or participates in JA signaling pathway that contributes to cuticular wax biosynthesis and cutin monomer formation in response to wounding. Significance Statement: Plant cuticle is a lipidic barrier composed of cuticular wax and cutin polymers. Cuticle plays a critical role in protecting plants from various biotic and abiotic stresses. Wounds due to mechanical damage or insect feeding are common and are potentially harmful to plants. However, the effect of wounding on plant cuticular wax and cutin monomer biosynthesis remains unclear. In our study, the findings present the validation that the Arabidopsis cuticle development was positively regulated by wounding mainly through the jasmonic acid (JA) signaling pathway. We also characterized the wound‐ and JA‐responsive gene CYP96A4, which is required for wound‐ and JA‐induced synthesis of cuticular wax and cutin monomer. [ABSTRACT FROM AUTHOR]

The plant cuticle, consisting of wax and cutin, is involved in adaptations to various environments. β-Ketoacyl-CoA synthases (KCSs) usually serve as a component of the fatty acid elongation complex that participates in the production of very long-chain fatty acids and provides precursors for the synthesis of various lipids, including wax; however, we recently reported that KCS3 and KCS12 negatively regulate wax biosynthesis. In this current study, we observed that unlike KCS3 -overexpressing (OE) lines, KCS12 -OE lines had fused floral organs because of abnormal cuticle biosynthesis. This prompted us to compare the functions of KCS3 and KCS12 during cuticle formation. Mutation of KCS3 caused greater effects on wax production, whereas mutation of KCS12 exerted more severe effects on cutin synthesis. The double-mutant kcs3 kcs12 had significantly increased wax and cutin contents compared to either single-mutant, suggesting that KCS12 and KCS3 have additive effects on cuticle biosynthesis. Cuticle permeability was greater for the double-mutant than for the single mutants, which ultimately led to increased susceptibility to drought stress and floral-organ fusion. Taken together, our results demonstrate the regulatory roles of KCS3 and KCS12 during cuticle biosynthesis, and show that maintaining KCS3 and KCS12 expression at certain levels is essential for the formation of a functional cuticle layer. [ABSTRACT FROM AUTHOR]

The plant cuticle, a structure primarily composed of wax and cutin, forms a continuous coating over most aerial plant surfaces. The cuticle plays important roles in plant tolerance to environmental stress, including stress imposed by drought. Some members of the 3-KETOACYL-COA SYNTHASE (KCS) family are known to act as metabolic enzymes involved in cuticular wax production. Here we report that Arabidopsis (Arabidopsis thaliana) KCS3, which was previously shown to lack canonical catalytic activity, instead functions as a negative regulator of wax metabolism by reducing the enzymatic activity of KCS6, a key KCS involved in wax production. We demonstrate that the role of KCS3 in regulating KCS6 activity involves physical interactions between specific subunits of the fatty acid elongation complex and is essential for maintaining wax homeostasis. We also show that the role of the KCS3–KCS6 module in regulating wax synthesis is highly conserved across diverse plant taxa from Arabidopsis to the moss Physcomitrium patens , pointing to a critical ancient and basal function of this module in finely regulating wax synthesis. [ABSTRACT FROM AUTHOR]

Summary: Plant cuticular wax accumulation limits nonstomatal transpiration and is regulated by external environmental stresses. DEWAX (DECREASE WAX BIOSYNTHESIS) plays a vital role in diurnal wax biosynthesis. However, how DEWAX expression is controlled and the molecular mechanism of wax biosynthesis regulated by the diurnal cycle remains largely unknown. Here, we identified two Arabidopsis MYB‐SHAQKYF transcription factors, MYS1 and MYS2, as new regulators in wax biosynthesis and drought tolerance.Mutations of both MYS1 and MYS2 caused significantly reduced leaf wax, whereas overexpression of MYS1 or MYS2 increased leaf wax biosynthesis and enhanced drought tolerance. Our results demonstrated that MYS1 and MYS2 act as transcription repressors and directly suppress DEWAX expression via ethylene response factor‐associated amphiphilic repression motifs.Genetic interaction analysis with DEWAX, SPL9 (SQUAMOSA PROMOTER BINDING PROTEIN‐LIKE 9), and CER1 (ECERIFERUM 1) in wax biosynthesis and under drought stresses demonstrated that MYS1 and MYS2 act upstream of the DEWAX‐SPL9 module, thus regulating CER1 expression. Expression analysis suggested that the diurnal expression pattern of DEWAX is partly regulated by MYS1 and MYS2.Our findings demonstrate the roles of two unidentified transcription repressors, MYS1 and MYS2, in wax biosynthesis and provide insights into the mechanism of diurnal cycle‐regulated wax biosynthesis. [ABSTRACT FROM AUTHOR]

Recent research into anion exchange membrane fuel cells (AEMFCs) highlights challenges in achieving high performance, primarily due to poor water management. This study delves into how the structure and thickness of the catalyst layer, specifically the pore design, affect AEMFC efficiency. Our study reveals that H 2 /O 2 AEMFC performance is significantly influenced by the distribution and structure of anode porous sizes, which affects water generation and transport kinetics. It has become evident that, instead of oxygen availability at the cathode, the primary factors constraining AEMFC performance are water supply through back-diffusion and water flooding at the anode. Notably, by controlling the carbon content of the anode catalyst layer to create gradient pores, we successfully alleviate mass transport limitations of gases in AEMFCs, while simultaneously improving water transport. Furthermore, insights from surface water transport and detailed phase field model analysis further confirmed that these gradient pores enhance water transportation rates. These results indicate that the fabrication of a porosity-gradient anode catalyst layer using carbon powder significantly increased the limit current density by 24 % (from 4.10 W cm−2 to 5.20 W cm−2) and the power density by 34.6 % (from 1.56 W cm−2 to 2.10 W cm−2), compared to the catalyst layer without carbon powder. • Carbon powder creates a gradient pore structure in the anode layer. • This gradient pore structure markedly boosts AEMFC performance. • Gradient pores boost capillary pressure and water transport in the catalyst layer. • The impact of catalyst layer microstructure on transport processes is deeply analyzed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tuning phases of MIL-100, MIL-110 and MIL-96 by applying formic acid as modulator. • Demonstrating the diversity of various ligands on node sites of MIL-110 and MIL-96. • Illustrating a highly flexible formate bonding site on Al 3 (OH) 3 unit of MIL-96. • Elucidating only a small fraction of node sites contributes to catalysis. Metal oxide cluster MOF nodes are a good platform to understand the reactivities and catalysis. MIL-96, MIL-100 and MIL-110 are drastically different in their node structures. Following our previous reported results for MIL-100, we report the modified synthesis and characterization of the node sites of MIL-110 and MIL-96 and their catalytic sites by using methanol dehydration as probe reaction. We show that these MOFs can be synthesized from the same solution by adding various amounts of formic acid as modulator. Herein, the chemistry of hydroxyl, formate and methoxy groups were used to probe the three MOFs' node sites. IR data show the bonding structures of these ligands are highly diverse, with reactivities and flexibilities depending on node sites. We identified terminal OH group and various µ 2 -OH groups in single, paired or hydrogen bonded modes on the MOF nodes. Formate ligands were introduced to the node sites during the synthesis or by a post treatment in formic acid/DMF solution. Surprisingly, the bonding modes of formate ligands on Al 3 (OH) 3 node structure of MIL-96 can be reversibly switched between monodentate and bidentate through a process induced by water molecules. Further, methoxy ligands—likely to be the intermediate for catalytic reaction—were also observed on the node sites under methanol dehydration conditions at 250 ℃. The activities of MIL-100 and MIL-96 for methanol dehydration determined by TOF per node were similar, both approximately 3-fold higher than that of MIL-110. The data suggests that catalytic sites incorporate adjacent vacancy and defect node sites, which constitute a minority among all observed MOF node sites. We foresee the opportunities in expanding the chemistry and understanding into other MOFs with metal oxide cluster nodes. [ABSTRACT FROM AUTHOR]

3-ketoacyl-CoA synthases (KCSs), as components of a fatty acid elongase (FAE) complex, play key roles in determining the chain length of very-long-chain fatty acids (VLCFAs). KCS6, taking a predominate role during the elongation from C26 to C28, is well known to play an important role in wax synthesis. KCS5 is one paralog of KCS6 and its role in wax synthesis remains unknown. Wax phenotype analysis showed that in kcs5 mutants, the total amounts of wax components derived from carbon 32 (C32) and C34 were apparently decreased in leaves, and those of C26 to C32 derivatives were obviously decreased in flowers. Heterologous yeast expression analysis showed that KCS5 alone displayed specificity towards C24 to C28 acids, and its coordination with CER2 and CER26 catalyzed the elongation of acids exceeding C28, especially displaying higher activity towards C28 acids than KCS6. BiLC experiments identified that KCS5 physically interacts with CER2 and CER26. Wax phenotype analysis of different organs in kcs5 and kcs6 single or double mutants showed that KCS6 mutation causes greater effects on the wax synthesis than KCS5 mutation in the tested organs, and simultaneous repression of both protein activities caused additive effects, suggesting that during the wax biosynthesis process, KCS5 and KCS6 play redundant roles, among which KCS6 plays a major role. In addition, simultaneous mutations of two genes nearly block drought-induced wax production, indicating that the reactions catalyzed by KCS5 and KCS6 play a critical role in the wax biosynthesis in response to drought. [ABSTRACT FROM AUTHOR]

• CH 4 and HCl vied for adsorption at the same active sites on the OC surface. • Service life of OC declined to 1136 h due to the formation of crystal islands. • Diffusion resistance of CH 4 into the inner region of HCl-treated OC was reduced. In chemical looping combustion (CLC) of coal, HCl has been demonstrated as the primary gaseous products of the chlorine in coal. Therefore, a comprehensive characterization of Cu-based oxygen carriers (OC) by HCl corrosion was meticulously conducted, including the activity retention, composition distribution and apparent morphology. The experiment consisted of three parts: (I) evaluating of the OC performance for 100 redox cycles with 7.8 vol% CH 4 ; (II) investigating HCl-corrosion of OC by adding 50 ppmv HCl with 7.1 vol% CH 4 for the subsequent 50 cycles; (III) regenerating of OC without HCl addition during the last 50 cycles. The reactivity of OC was attenuating via the HCl addition during the 101st–150th cycles (part II) due to the competition adsorption between HCl and CH 4 , especially for the partly reduced OC. While, in part III, the reactivity performance of OC was partially recovered because of the abundant cracks on the surface of OC particles which ensured the sufficient gas–solid contact. It should be noted that the single particle hardness index and service life were irreversibly decreased for the HCl-treated OC. Moreover, OC particles were fragmented and the inside Al 2 O 3 balls were exposed on the surface of the HCl-treated OC in SEM image. This work will contribute to understanding the mechanism of Cl-corrosive OC and designing the Cl-resistant OC. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work provides quantitative resolution of defect and structural vacancy sites on Al 3 O nodes of MIL-100(Al) and demonstrates the cooperative role of neighboring defect and structural vacancy sites. • Post-treatment of MIL-100(Al) with a formic acid/DMF led to replacement of ligands on defects and extra-framework BTC3- on vacancy sites by formate. • This work illustrates the chemistry of formate, methoxy and hydroxyl ligands on Al 3 O nodes. • The catalytic sites for methanol dehydation are inferred to be two adjacent sites—a defect site and its neighboring vacancy site—with methoxy reaction intermediates bonded on each site. The metal–organic framework (MOF) MIL-100, which incorporates vacancy sites on Al 3 O nodes, was synthesized with various densities of missing-benzene-1,3,5-tricarboxylate (BTC3−)-linker defect sites by using HNO 3 or acetic acid as a modulator. We report data that resolve the effects on reactivity of the node vacancies and defects that are neighbors of each other. For example, extra-framework BTC3− ligands were bonded to one vacancy site per node, and modulator-derived NO 3 − and acetate ligands were bonded in various ratios to defect sites. In reactions with formic acid, these ligands were replaced with monodentate and bidentate formates. The ligands on defects were found to be more reactive than those on vacancies. The MOF was used to catalyze methanol dehydration at 220 °C and 1 bar in a flow reactor, and the catalytic activity increased with increasing numbers of defects and with replacement of extra-framework BTC3- with formate. Catalysis started as methanol reacted with formate ligands to form methyl formate, which desorbed, leaving methoxy groups on the nodes—and these became catalytic reaction intermediates. IR spectra and catalyst performance data show that that catalysis proceeds as bidentate methoxy bonded to a defect site reacts with monodentate methoxy bonded to a neighboring vacancy site. Having a high density of these paired sites, MIL-100(Al) is markedly more active catalytically than the MOF MIL-53, in which these essential sites are mostly isolated. Deactivation of MIL-100 during catalysis resulted from self-inhibition, as bidentate methoxy ligands were replaced with μ 2 -OH ligands formed from water produced in the dehydration reaction. The results highlight the role of pair sites on MOF nodes for catalyzing a reaction that involves a bimolecular step, indicating how to control the catalytic sites. We thus foresee opportunities to tailor MOF catalytic properties for reactions involving various numbers of catalytic sites on the nodes. [ABSTRACT FROM AUTHOR]

The efficient nanocomposite of CoFe2O4 diatomite for electromagnetic microwave adsorption was assembled by CoFe2O4 nanoparticles (NPs) and diatomite via a simple citric acid-nitrate sol-gel auto-combustion method. The electronic microscopy results show that the magnetic CoFe2O4 NPs are uniformly dispersed in the surface and porous structure of diatomite to form stable CoFe2O4/diatomite nanocomposite. The magnetic and dielectric properties with various mass ratios of CoFe2O4 to diatomite was investigated. It was showed that nanocomposite of CoFe2O4/ diatomite has strong superparamagnetic and electromagnetic microwave absorbing properties with optimized conditions of coercive force of 837.07 Oe, the saturation magnetization of 96.5 emu/g, and the remanence ratio (Mr/Ms) of 0.52, respectively. The maximum reflection loss is -12dB, and <-10dB frequency ranges from 10Hz to 12Hz when the ratio of CoFe2O4 to Diatomite is 1:10. The results indicate that CoFe2O4/diatomite composites can be used as the highly efficient microwave absorption materials, which expanded the application field of diatomite-based functional nanomaterials. [ABSTRACT FROM AUTHOR]

Anion exchange membrane fuel cells (AEMFCs) are a promising power source due to zero emissions and high efficiency, and low precious metal loading. However, water management remains a significant issue affecting cell performance and durability. In this study, we develop a multi-physics model to investigate and optimize transport phenomena under various operational conditions and microstructure parameters. The agglomerate model is optimized to consider the influence of anode flooding and cathode drying in electrochemical reactions, and the simulation is validated with experimental results. Our findings indicate that an optimal anode inlet gas relative humidity of 80% achieved a tradeoff between anode flooding and ionic conductivity, resulting in a maximal power density of 758.9 mW/cm2. To alleviate anode flooding, we optimize the microstructure of the anode gas diffusion layer, significantly improving maximal power density to 833.4 mW/cm2 by increasing the contact angle to 130°. The optimal porosity achieves a balance between the transport of liquid water and electron. Large pore diameter and small thickness lead to a slighter anode flooding and higher maximal power density. In summary, our study provides insights into the transport behavior of multi-phase water, reactant gas, ion, and electron to guide the design of high-performance AEMFCs. • AEMFCs model is developed and validated with experimental data. • A modified agglomerate model with a catalyst utilization factor is proposed. • Anode flooding and cathode drying phenomenon are analyzed in detail. • Microstructures of GDL are optimized to enhance liquid water transport. [ABSTRACT FROM AUTHOR]

[Display omitted] • The concept of "metal coverage" is put forward to link with reversal tolerance. • The higher metal coverage causes a longer reversal time and slower degradation rate. • Ir/Pt/C shows more than 50 times longer reversal time than Pt/Ir/C counterparts. • Ir/Pt/C displays two orders of magnitude slower degradation rate than Pt/Ir/C. Anode cell reversal, which is caused by fuel starvation, poses a great threat to the durability of proton exchange membrane fuel cells. Commercially, iridium oxide or iridium is applied to boost oxygen evolution reaction, which alleviates carbon corrosion and protects the catalyst layer structure. However, the key factors that affect the anti-reversal ability and the interaction between Pt, Ir, and carbon support are still unclear. Hence, we systematically studied the performance using three typical carbon supports with three metal contents and different metal deposition orders by experiments and model calculations. A new parameter, "relative metal coverage", is put forward to evaluate and predict the anti-reversal ability, showing higher relative metal coverage results in a longer reversal time and lower polarization performance degradation rate. Typically, only a 15.5% polarization performance loss after 1700 mins reversal time when the relative metal coverage of high metal content Ir/Pt/Super P anode is one. The results suggest that increasing relative metal coverage is a practical approach to improve reversal tolerance and provide new insights into the reversal tolerant anodes design. [ABSTRACT FROM AUTHOR]

Machinery degradation assessment can offer meaningful prognosis and health management information. Although numerous machine prediction models based on artificial intelligence have emerged in recent years, they still face a series of challenges: (1) Many models continue to rely on manual feature extraction. (2) Deep learning models still struggle with long sequence prediction tasks. (3) Health indicators are inefficient for remaining useful life (RUL) prediction with cross-operational environments when dealing with high-dimensional datasets as inputs. This research proposes a health indicator construction methodology based on a transformer self-attention transfer network (TSTN). This methodology can directly deal with the high-dimensional raw dataset and keep all the information without missing when the signals are taken as the input of the diagnosis and prognosis model. First, we design an encoder with a long-term and short-term self-attention mechanism to capture crucial time-varying information from a high-dimensional dataset. Second, we propose an estimator that can map the embedding from the encoder output to the estimated degradation trends. Then, we present a domain discriminator to extract invariant features from different machine operating conditions. Case studies were carried out using the FEMTO-ST bearing dataset, and the Monte Carlo method was employed for RUL prediction during the degradation process. When compared to other established techniques such as the RNN-based RUL prediction method, convolutional LSTM network, Bi-directional LSTM network with attention mechanism, and the traditional RUL prediction method based on vibration frequency anomaly detection and survival time ratio, our proposed TSTN method demonstrates superior RUL prediction accuracy with a notable SCORE of 0.4017. These results underscore the significant advantages and potential of the TSTN approach over other state-of-the-art techniques. [ABSTRACT FROM AUTHOR]

• A comprehensive transient axial-symmetric model was developed for the solar thermochemical reactor. • The electrochemical oxygen pump (EOP) with the lowest energy penalty was employed to reduce the oxygen partial pressure. • Reactor performance for EOP scheme and other two traditional schemes (i.e., SG scheme and VP scheme) was compared in detail for different DNI conditions. • Two control strategies were proposed to increase the solar-to-fuel efficiency. Solar thermochemical water splitting provides an efficient route for converting solar energy into renewable fuels. The operation of solar thermochemical reactor under real on-sun condition requires in-depth understanding of its dynamic behaivor under fluctuating direct normal irradiation (DNI). In this work, we developed a 2D axial-symmetric multi-physical model to assess the reactor's dynamic behavior with three oxygen removing technologies electrochemical oxygen pump (EOP), sweep gas (SG), and vacuum pump (VP), under varying solar irradiations. To alleviate the negative effect of decreased DNI, two control strategies (CS) including varying operational conditions for oxygen removing technologies (CS1) and replacing the reduction step with the oxidation step (CS2) were conducted. We found that CS1 was only effective when DNI reduction was larger than 75 % over the whole reduction step (case 2). In general, CS2 can be implemented to alleviate the efficiency decrease for all DNI variations expect for the case 2 in this study. Especially, CS2 significantly increased the solar-to-fuel efficiency compared to the case without control strategy for the reduced DNI from 1000 W/m2 to 500 W/m2 during the whole reduction step. The reactor dynamic behavior in response to the daily DNI variations is also reported which shows that the efficiency profiles are highly in line with the DNI profile. This modeling work as well as proposed control strategies can be used to guide the design and control of solar thermochemical reactors under realistic conditions and hence for better assessing the performance of the reactor in practice. [ABSTRACT FROM AUTHOR]

• A high fidelity and cost-effective 3D model is developed for high-temperature solar cavity receivers. • A novel radiative transfer model based on modified P1 approximation was proposed and implemented. • Effects of material, geometrical, and operational conditions on solar thermal conversion performance are investigated. • The solar-to-thermal efficiency can be improved by 23% with optimized operational conditions. High-temperature solar receivers are core components in concentrated solar energy utilization systems. The rational design of solar receivers relies on the fundamental understanding of coupled physics across various scales. We developed a numerical model to assess the solar thermal conversion behaviour under various porous structure designs, material choices, geometrical designs, as well as operational conditions. The 3D model solves a coupled set of equations accounting for mass, momentum, and energy conservations in the cavity and porous media domains. We have optimized the radiative transfer model to resolve the participating behaviour only in the porous domain and non-participating behaviour only for cavity and window surfaces. This cost-effective model enables fast performance evaluation for various design parameters. The windowless receiver, in general, shows higher solar-to-thermal efficiency compared to the window receiver. This superiority in optical efficiency for the windowless case can be surpassed by the window case at high incident solar power with a fixed outlet temperature. For porous media structure, both window and windowless receivers are optimized by the porosity and pore diameter. The solar-to-thermal efficiency was slightly influenced by the cavity inclination. Large porous layer thickness leads to reduced performance for the windowless receivers, while the efficiency reaches a plateau for the window receiver at large thickness. We have provided a comprehensive modeling framework for the design of solar receivers for high-temperature applications using concentrated solar energy which can be easily adapted for receiver under a wide range of designs and operation conditions. [ABSTRACT FROM AUTHOR]

Cutin and wax are the main precursors of the cuticle that covers the aerial parts of plants and provide protection against biotic and abiotic stresses. Long-chain acyl-CoA synthetases (LACSs) play diversified roles in the synthesis of cutin, wax, and triacylglycerol (TAG). Most of the information concerned with LACS functions is obtained from model plants, whereas the roles of LACS genes in Glycine max are less known. Here, we have identified 19 LACS genes in Glycine max, an important crop plant, and further focused our attention on 4 LACS2 genes (named as GmLACS2-1, 2, 3, 4, respectively). These GmLACS2 genes display different expression patterns in various organs and also show different responses to abiotic stresses, implying that these genes might play diversified functions during plant growth and against stresses. To further identify the role of GmLACS2-3, greatly induced by abiotic stresses, we transformed a construct containing its full length of coding sequence into Arabidopsis. The expression of GmLACS2-3 in an Arabidopsis atlacs2 mutant greatly suppressed its phenotype, suggesting it plays conserved roles with that of AtLACS2. The overexpression of GmLACS2-3 in wild-type plants significantly increased the amounts of cutin and suberin but had little effect on wax amounts, indicating the specific role of GmLACS2-3 in the synthesis of cutin and suberin. In addition, these GmLACS2-3 overexpressing plants showed enhanced drought tolerance. Taken together, our study deepens our understanding of the functions of LACS genes in different plants and also provides a clue for cultivating crops with strong drought resistance. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of the corrosion fatigue life prediction model for the 7050 aluminum alloy, this study presents a corrosion fatigue life prediction model based on back-propagation (BP) neural network optimized by improved grey wolf optimization (IGWO) algorithm that takes into account different sampling orientations and stress magnitudes. The model determines the mapping relationship between corrosion fatigue life, sample direction, and stress level. It also compares the improved grey wolf optimization-backpropagation (IGWO-BP) prediction error with three other models: BP, particle swarm optimization-back propagation (PSO-BP), and genetic algorithm-backpropagation (GA-BP). The IGWO-BP model's performance measures are as follows: a determination coefficient (R2) of 0.9740, a mean absolute error (MAE) of 0.0479, a root mean square error (RMSE) of 0.0596, and a mean absolute percentage error (MAPE) of 0.9443%. For both the training and test sets, the predicted results are within an error margin of 1.5 times. When compared with the conventional BP neural network, the R2 of IGWO-BP is increased by 5.69%, and the RMSE, MAE, and MAPE of IGWO-BP are the smallest, reduced by 26.24, 26.19, and 26.72%, respectively. [ABSTRACT FROM AUTHOR]

Summary: Iso‐branched wax compounds are well known in plants, but their biosynthetic pathways are still mostly unknown. It has been speculated that branched waxes are derived from branched‐chain amino acid (BCAA) catabolism, but the evidence for this is very limited.Gas chromatography‐flame ionisation detection (GC‐FID) analysis revealed that mutations in two subunits of the branched‐chain ketoacid dehydrogenase (BCKDH) complex, a key enzyme complex in the degradation of BCAAs, significantly decreased the amounts of branched wax compounds, indicating that BCAA degradation may be integral to the synthesis of iso‐branched wax. Substrate feeding studies further revealed that the metabolic precursor of iso‐branched wax compounds is isobutyric acid (iBA), which is derived from valine degradation in Arabidopsis.We also isolated a novel mutant and found that its branched wax deficient phenotype could not be rescued by iBA. Map‐based cloning together with complementation analysis revealed that mutation in ACYL‐ACTIVATING ENZYME 9 (AAE9) is responsible for this phenotype.Genetic and enzyme activity analysis demonstrated that AAE9 is located downstream of the BCAA degradation pathway, and that it activates iBA to isobutyryl‐CoA for use on branched wax synthesis. Taken together, our study demonstrates that AAE9 is a key factor connecting BCAA catabolism with branched wax biosynthesis. [ABSTRACT FROM AUTHOR]

In plants, Long-chain acyl-CoA synthetases (LACSs) play key roles in activating fatty acids to fatty acyl-CoA thioesters, which are then further involved in lipid synthesis and fatty acid catabolism. LACSs have been intensively studied in Arabidopsis , but its evolutionary relationship in green plants is unexplored. In this study, we performed a comprehensive genome-wide analysis of the LACS gene family across green plants followed by phylogenetic clustering analysis, gene structure determination, detection of conserved motifs, gene expression in tissues and subcellular localization. Our results identified LACS genes in 122 plant species including algae, low land plants (i.e., mosses and lycophytes), monocots, and eudicots. In total, 697 sequences were identified, and 629 sequences were selected because of alignment and some duplication errors. The retrieved amino acid sequences ranged from 271 to 1056 residues and diversified in intron/exon patterns in different LACSs. Phylogenetic clustering grouped LACS gene family into six major clades with distinct potential functions. This classification is well supported by examining gene structure and conserved motifs. Also, gene expression analysis and subcellular localization substantiate with clade division in the phylogeny, indicating that the evolutionary pattern is visible in their functionality. Additionally, experimental analysis of lacs2 mutant validated that LACS2 plays key roles in suberin synthesis. Thus, our study not only provides an evolutionary mechanism underlying functional diversification but also lays the foundation for further elucidation of the LACS gene family. • This is the first genome-wide identification of 629 LACSs genes in 122 plant species. • Phylogenetic analysis of LACSs genes shows six major clades with potential distinct functions. • LACSs genes present specific expression patterns across different tissues with different level. [ABSTRACT FROM AUTHOR]

Scour around a circular monopile in coastal regions has been investigated extensively over the past decades, but the time development of scour depth around an offshore-wind monopile under large current–wave ratio still lacks a predictive model. By considering the conservation of sand volume and adopting the conventional exponential law for temporal variation, a semi-empirical model, which has three parameters, i.e., an equilibrium scour depth, a shape coefficient and a scour characteristic time scale, is developed for predicting the time development of scour depth around a monopile under live-bed conditions of combined wave–current flows. A series of laboratory experiments was conducted in current-only and wave–current flows to obtain data for model calibration and validation. Experimental results indicate that adding weak waves on current accelerates scour development, which is successfully captured by the proposed model through using the far-field bottom shear stress as a key model input. The overall model inaccuracy is within 25%, and the model's applicability is further confirmed by field measurements from an offshore wind farm in east China. This model can help to determine the timing of installing scour protection around offshore monopiles, especially for the circumstances with very strong local sediment transport (live-bed). • A new model for scour time development around a circular pile is proposed. • A set of scour tests was conducted in live-bed conditions for calibration and validation. • A field study was carried out for an offshore monopile wind farm in eastern China. [ABSTRACT FROM AUTHOR]

The human genome is diploid, and knowledge of the variants on each chromosome is important for the interpretation of genomic information. Here we report the assembly of a haplotype-resolved diploid genome without using a reference genome. Our pipeline relies on fosmid pooling together with whole-genome shotgun strategies, based solely on next-generation sequencing and hierarchical assembly methods. We applied our sequencing method to the genome of an Asian individual and generated a 5.15-Gb assembled genome with a haplotype N50 of 484 kb. Our analysis identified previously undetected indels and 7.49 Mb of novel coding sequences that could not be aligned to the human reference genome, which include at least six predicted genes. This haplotype-resolved genome represents the most complete de novo human genome assembly to date. Application of our approach to identify individual haplotype differences should aid in translating genotypes to phenotypes for the development of personalized medicine. [ABSTRACT FROM AUTHOR]

Despite an increase in the number of molecular epidemiological studies conducted in recent years to evaluate the association between human papillomavirus (HPV) and the risk of breast carcinoma, these studies remain inconclusive. Here we aim to detect HPV DNA in various tissues from patients with breast carcinoma using the method of HPV capture combined with massive paralleled sequencing (MPS). To validate the confidence of our methods, 15 cervical cancer samples were tested by PCR and the new method. Results showed that there was 100% consistence between the two methods.DNA from peripheral blood, tumor tissue, adjacent lymph nodes and adjacent normal tissue were collected from seven malignant breast cancer patients, and HPV type 16(HPV16) was detected in 1/7, 1/7, 1/7and 1/7 of patients respectively. Peripheral blood, tumor tissue and adjacent normal tissue were also collected from two patients with benign breast tumor, and 1/2, 2/2 and 2/2 was detected to have HPV16 DNA respectively. MPS metrics including mapping ratio, coverage, depth and SNVs were provided to characterize HPV in samples. The average coverage was 69% and 61.2% for malignant and benign samples respectively. 126 SNVs were identified in all 9 samples. The maximum number of SNVs was located in the gene of E2 and E4 among all samples. Our study not only provided an efficient method to capture HPV DNA, but detected the SNVS, coverage, SNV type and depth. The finding has provided further clue of association between HPV16 and breast cancer. [ABSTRACT FROM AUTHOR]

[Display omitted] • CHSD and lactulose ameliorate STC through different mechanisms. • CHSD has a better effect on community diversity and richness than lactulose. • CHSD and lactulose result in differences in the SCFA composition in faeces. • CHSD and lactulose elevate stimulatory neurotransmitters and reduce VIP in serum. Slow transit constipation (STC) has become an epidemic medical problem. There are several kinds of drugs for constipation; however, each drug has its limitations. The gut microbiota has a close relationship with STC. Lactulose is an effective drug for constipation because it is a kind of bulking laxative and microbioecologic, and it relieves the syndromes of STC. We found that the Chinese Herb Solid Drink (CHSD), which contains medicine food homologous materials such as psyllium husk, sweet almond, semen sesami nigrum, and hemp seed, has a similar effect on relieving constipation as lactulose, although it has different effects on the gut microbiota. We investigated the mechanisms of CHSD in rats with STC, induced by diphenoxylate, via constipation index and enzyme linked immunosorbent assay (ELISA) analyses using serum and 16S rDNA amplicon and gas chromatography-mass spectroscopy (GC–MS). CHSD enhanced the relative abundance of some types of gut microbiota, such as Blautia , Ruminococcus , Roseburia, Coprococcus, Lachnospira, and Phascolarctobacterium , while lactulose enhanced the relative abundance of Blautia, Phascolarctobacterium , Eubacterium , and Akkernansia in diphenoxylate-induced STC rats. Both CHSD and lactulose enhanced the level of short-chain fatty acids in the faeces of rats; however, the composition of those were different between the two drugs. From the perspective of the gut neuroendocrine system, both CHSD and lactulose could elevate neurotransmitters, such as motilin (MTL) and substance P (SP), which promote intestinal peristalsis and reduce the expression of vasoactive intestinal peptide, which inhibits intestinal peristalsis in the serum of STC rats. CHSD could elevate gastrin expression, which also promoted intestinal peristalsis in serum, while lactulose did not have this effect. Our findings suggest that CHSD may be an effective and safe therapeutic choice for STC. [ABSTRACT FROM AUTHOR]