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Natural products, known for their environmental safety, are regarded as a significant basis for the modification and advancement of fungicides. Melatonin, as a low‐cost natural indole, exhibits diverse biological functions, including antifungal activity. However, its potential as an antifungal agent has not been fully explored. In this study, a series of melatonin derivatives targeting the mitogen‐activated protein kinase (Mps1) protein of fungal pathogens were synthesized based on properties of melatonin, among which the trifluoromethyl‐substituted derivative Mt‐23 exhibited antifungal activity against seven plant pathogenic fungi, and effectively reduced the severity of crop diseases, including rice blast, Fusarium head blight of wheat and gray mold of tomato. In particular, its EC50 (5.4 µM) against the rice blast fungus Magnaporthe oryzae is only one‐fourth that of isoprothiolane (22 µM), a commercial fungicide. Comparative analyzes revealed that Mt‐23 simultaneously targets the conserved protein kinase Mps1 and lipid protein Cap20. Surface plasmon resonance assays showed that Mt‐23 directly binds to Mps1 and Cap20. In this study, we provide a strategy for developing antifungal agents by modifying melatonin, and the resultant melatonin derivative Mt‐23 is a commercially valuable, eco‐friendly and broad‐spectrum antifungal agent to combat crop disease. [ABSTRACT FROM AUTHOR]

Large-amplitude internal solitary waves were recently observed in a coastal plain estuary and were hypothesized to evolve from an internal lee wave generated at the channel–shoal interface. To test this mechanism, a 3D nonhydrostatic model with nested domains and adaptive grids was used to investigate the generation of the internal solitary waves and their subsequent nonlinear evolution. A complex sequence of wave propagation and transformation was documented and interpreted using the nonlinear wave theory based on the Korteweg–de Vries equation. During the ebb tide a mode-2 internal lee wave is generated by the interaction between lateral flows and channel–shoal topography. This mode-2 lee wave subsequently propagates onto the shallow shoal and transforms into a mode-1 wave of elevation as strong mixing on the flood tide erases stratification in the bottom boundary layer and the lower branch of the mode-2 wave. The mode-1 wave of elevation evolves into an internal solitary wave due to nonlinear steepening and spatial changes in the wave phase speed. As the solitary wave of elevation continues to propagate over the shoaling bottom, the leading edge moves ahead as a rarefaction wave while the trailing edge steepens and disintegrates into a train of rank-ordered internal solitary waves, due to the combined effects of shoaling and dispersion. Strong turbulence in the bottom boundary layer dissipates wave energy and causes the eventual destruction of the solitary waves. In the meantime, the internal solitary waves can generate elevated shear and dissipation rate in local regions. Significance Statement: In the coastal ocean nonlinear internal solitary waves are widely recognized to play an important role in generating turbulent mixing, modulating short-term variability of nearshore ecosystem, and transporting sediment and biochemical materials. However, their effects on shallow and stratified estuaries are poorly known and have been rarely studied. The nonhydrostatic model simulations presented in this paper shed new light into the generation, propagation, and transformation of the internal solitary waves in a coastal plain estuary. [ABSTRACT FROM AUTHOR]

Melatonina natural harmless molecule—displays versatile roles in human health and crop disease control such as for rice blast. Rice blast, caused by the filamentous fungus Magnaporthe oryzae, is one devastating disease of rice. Application of fungicides is one of the major measures in the control of various crop diseases. However, fungicide resistance in the pathogen and relevant environmental pollution are becoming serious problems. By screening for possible synergistic combinations, here, we discovered an eco‐friendly combination for rice blast control, melatonin, and the fungicide isoprothiolane. These compounds together exhibited significant synergistic inhibitory effects on vegetative growth, conidial germination, appressorium formation, penetration, and plant infection by M. oryzae. The combination of melatonin and isoprothiolane reduced the effective concentration of isoprothiolane by over 10‐fold as well as residual levels of isoprothiolane. Transcriptomics and lipidomics revealed that melatonin and isoprothiolane synergistically interfered with lipid metabolism by regulating many common targets, including the predicted isocitrate lyase‐encoding gene MoICL1. Furthermore, using different techniques, we show that melatonin and isoprothiolane interact with MoIcl1. This study demonstrates that melatonin and isoprothiolane function synergistically and can be used to reduce the dosage and residual level of isoprothiolane, potentially contributing to the environment‐friendly and sustainable control of crop diseases. [ABSTRACT FROM AUTHOR]

Melatonin is a low‐cost natural small indole molecule with versatile biological functions. However, melatonin's fungicidal potential has not been fully exploited, and the mechanism remains elusive. Here, we report that melatonin broadly inhibited 13 plant pathogens. In the rice blast fungal pathogen Magnaporthe oryzae, melatonin inhibited fungal growth, formation of infection‐specific structures named appressoria, and plant infection, reducing disease severity. Melatonin entered fungal cells efficiently and colocalized with the critical mitogen‐activated protein kinase named Mps1, suppressing phosphorylation of Mps1. Melatonin's affinity for Mps1 via two hydrogen bonds was demonstrated using surface plasmon resonance and chemical modifications. To improve melatonin's efficiency, we obtained 20 melatonin derivatives. Tert‐butyloxycarbonyl melatonin showed a 25‐fold increase in fungicidal activities, demonstrating the feasibility of chemical modifications in melatonin modification. Our study demonstrated the broad‐spectrum fungicidal effect of melatonin by suppressing Mps1 as one of the targets. Through further systematic modifications, developing an eco‐friendly melatonin derivative of commercial values for agricultural applications appears promising. [ABSTRACT FROM AUTHOR]

Using an idealized channel representative of a coastal plain estuary, we conducted numerical simulations to investigate the generation of internal lee waves by lateral circulation. It is shown that the lee waves can be generated across all salinity regimes in an estuary. Since the lateral currents are usually subcritical with respect to the lowest mode, mode-2 lee waves are most prevalent but a hydraulic jump may develop during the transition to subcritical flows in the deep channel, producing high energy dissipation and strong mixing. Unlike flows over a sill, stratified water in the deep channel may become stagnant such that a mode-1 depression wave can form higher up in the water column. With the lee wave Froude number above 1 and the intrinsic wave frequency between the inertial and buoyancy frequency, the lee waves generated in coastal plain estuaries are nonlinear waves with the wave amplitude Δh scaling approximately with V / N ¯ , where V is the maximum lateral flow velocity and N ¯ is the buoyancy frequency. The model results are summarized using the estuarine classification diagram based on the freshwater Froude number Frf and the mixing parameter M. The Δh decreases with increasing Frf as stronger stratification suppresses waves, and no internal waves are generated at large Frf. The Δh initially increases with increasing M as the lateral flows become stronger with stronger tidal currents, but decreases or saturates to a certain amplitude as M further increases. This modeling study suggests that lee waves can be generated over a wide range of estuarine conditions. [ABSTRACT FROM AUTHOR]

We present an approach in the framework of abstract interpretation to analyze list-manipulating programs by combining shape and numerical abstractions. The analysis automatically divides a list into non-overlapping list segments according to the reachability property of pointer variables to list nodes. The list nodes in each segment are abstracted by a bit-vector wherein each bit corresponds to a pointer variable and indicates whether the nodes can be reached by that pointer variable. Moreover, for each bit-vector, we introduce an auxiliary integer variable, namely a counter variable, to record the number of nodes in the segment abstracted by that bit-vector. On this basis, we leverage the power of numerical abstractions to discover numerical relations among counter variables, so as to infer relational length properties among list segments. Furthermore, we show how our approach works for circular lists. Our approach stands out in its ability to find intricate properties that involve both shape and numerical information, which are important for checking program properties such as memory safety. A prototype is implemented and preliminary experimental results are encouraging. [ABSTRACT FROM AUTHOR]

Plant pathogens cause devastating diseases, leading to serious losses to agriculture. Mechanistic understanding of pathogenesis of plant pathogens lays the foundation for the development of fungicides for disease control. Mitophagy, a specific form of autophagy, is important for fungal virulence. The role of cardiolipin, mitochondrial signature phospholipid, in mitophagy and pathogenesis is largely unknown in plant pathogenic fungi. The functions of enzymes involved in cardiolipin biosynthesis and relevant inhibitors were assessed using a set of assays, including genetic deletion, plant infection, lipidomics, chemical‐protein interaction, chemical inhibition, and field trials. Our results showed that the cardiolipin biosynthesis‐related gene MoGEP4 of the rice blast fungus Magnaporthe oryzae regulates growth, conidiation, cardiolipin biosynthesis, and virulence. Mechanistically, MoGep4 regulated mitophagy and Mps1‐MAPK phosphorylation, which are required for virulence. Chemical alexidine dihydrochloride (AXD) inhibited the enzyme activity of MoGep4, cardiolipin biosynthesis and mitophagy. Importantly, AXD efficiently inhibited the growth of 10 plant pathogens and controlled rice blast and Fusarium head blight in the field. Our study demonstrated that MoGep4 regulates mitophagy, Mps1 phosphorylation and pathogenesis in M. oryzae. In addition, we found that the MoGep4 inhibitor, AXD, displays broad‐spectrum antifungal activity and is a promising candidate for fungicide development. Summary Statement: This study demonstrated that MoGep4 regulates mitophagy, Mps1 activation and pathogenesis in Magnaporthe oryzae. Additionally, we found that the MoGep4 inhibitor, alexidine dihydrochloride, displays broad‐spectrum antifungal activity and is effective in disease control in the field. [ABSTRACT FROM AUTHOR]

Sclerospora graminicola (Sacc.) Schroeter is a biotrophic pathogen of foxtail millet (Setaria italica) and increasingly impacts crop production. We explored the main factors for symptoms such as dwarfing of diseased plants and the "hedgehog panicle" by determining panicle characteristics of varieties infected with S. graminicola and analyzing the endogenous hormone-related genes in leaves of Jingu 21. Results indicated that different varieties infected by S. graminicola exhibited various symptoms. Transcriptome analysis revealed that the ent-copalyl diphosphate synthetase (CPS) encoded by Seita.2G144900 and ent-kaurene synthase (KS) encoded by Seita.2G144400 were up-regulated 4.7-fold and 2.8-fold, respectively. Results showed that the biosynthesis of gibberellin might be increased, but the gibberellin signal transduction pathway might be blocked. The abscisic acid (ABA) 8′-hydroxylase encoded by Seita.6G181300 was continuously up-regulated by 4.2-fold, 2.7-fold, 14.3-fold, and 12.9-fold from TG1 to TG4 stage, respectively. Seita.2G144900 and Seita.2G144400 increased 79-fold and 51-fold, respectively, at the panicle development stage, promoting the formation of a "hedgehog panicle". Jasmonic acid-related synthesis enzymes LOX2s, AOS, and AOC were up-regulated at the early stage of infection, indicating that jasmonic acid played an essential role in early response to S. graminicola infection. The expression of YUC-related genes of the auxin synthesis was lower than that of the control at TG3 and TG4 stages, but the amidase encoded by Seita.2G313400 was up-regulated by more than 30-fold, indicating that the main biosynthesis pathway of auxin had changed. The results suggest that there was co-regulation of the hormone pathways during the infection of foxtail millet by S. graminicola. [ABSTRACT FROM AUTHOR]

Summary: As phospholipids of cell membranes, phosphatidylethanolamine (PE) and phosphatidylserine (PS) play crucial roles in glycerophospholipid metabolism. Broadly, some phospholipid biosynthesis enzymes serve as potential fungicide targets. Therefore, revealing the functions and mechanism of PE biosynthesis in plant pathogens would provide potential targets for crop disease control.We performed analyses including phenotypic characterizations, lipidomics, enzyme activity, site‐directed mutagenesis, and chemical inhibition assays to study the function of PS decarboxylase‐encoding gene MoPSD2 in rice blast fungus Magnaporthe oryzae.The Mopsd2 mutant was defective in development, lipid metabolism, and plant infection. The PS level increased while PE decreased in Mopsd2, consistent with the enzyme activity. Furthermore, chemical doxorubicin inhibited the enzyme activity of MoPsd2 and showed antifungal activity against 10 phytopathogenic fungi including M. oryzae and reduced disease severity of two crop diseases in the field. Three predicted doxorubicin‐interacting residues are important for MoPsd2 functions.Our study demonstrates that MoPsd2 is involved in de novo PE biosynthesis and contributes to the development and plant infection of M. oryzae and that doxorubicin shows broad‐spectrum antifungal activity as a fungicide candidate. The study also implicates that bacterium Streptomyces peucetius, which biosynthesizes doxorubicin, could be potentially used as an eco‐friendly biocontrol agent. [ABSTRACT FROM AUTHOR]

Peng, J.; Zhou, Z., and Li, R., 2015. A collaborative berth allocation problem with multiple ports based on Genetic Algorithm. As a part of scheduling, Berth Allocation Problem can be considered as a problem of minimizing the total service time of vessels which berth at the port. The purpose is to optimize the efficiency of the port and the passing rate of vessels. The balanced deployment issues of yards can be transformed into considered as an equilibrium assignment of yard storage. The purpose is to give the loading vessels more choices to choose their best lanes and enhance the efficiency of the yard, as well as reduce the transportation costs. This paper combines berth allocation and yard assignment problems to build a collaborative berth allocation model with multiple ports under the background of bulk ports. The objective of this model consists of two parts: The minimization of total service time of vessels and the equilibrium assignment of yard storage. This paper uses two approaches to solve the above-mentioned mixed integer nonlinear programming problems: IBM ILOG CPLEX and Genetic Algorithm. According to the actual data of Majishan Port and Ore Transfer Terminal of Lake Shulang, many numerical experiments are conducted. This paper analyzes and compares these two approaches and proves the validity and accuracy of Genetic Algorithm and CPLEX. The model and the analysis procedure of numerical experiments are of certain reference value and practical significance on the management of berth allocation and yard assignment with multiple ports. [ABSTRACT FROM AUTHOR]

The understanding of fouling behaviors and mechanism is critical for membrane fouling that is a bottleneck for the sustainable application of membrane technology. Therefore, it is essential to develop new analytical tools that can in situ characterize membrane fouling processes during filtration. In this work, we demonstrate a capability of high-resolution large-scale in situ visualization that can rapidly differentiate foulants and their temporal-spatial-distributions on/in/over the membrane matrix during filtration process based on multi-color light sheet fluorescence imaging platform. The rapid-evolving fouling process of different foulants were directly monitored and analyzed during the ultrafiltration of bovine serum albumin (BSA), dextran and their mixture solutions. Inner adsorption was found to play a more critical role for dextran-induced fouling on polymeric membranes compared with BSA-induced fouling. During the ultrafiltration of BSA/dextran mixture solutions, BSA was directly observed as the major contributor to the decrease of permeate flux, which could be employed as a complementary evidence for the interfacial free energy calculations during membrane fouling and vice versa. This work provides new insights into combined membrane fouling process and offers a highly-sensitive, non-invasive characterization tool for a wide range of explorations in membrane-based processes and interfacial processes. [Display omitted] In situ large-scale characterization of combined membrane fouling behaviors Strong relations between flux decline rate and foulant distributions in/on membrane Direct observation of key foulant in combined fouling process Facilitation of exploring interfacial processes (dynamic and thermodynamic) [ABSTRACT FROM AUTHOR]

As with the majority of the hemibiotrophic fungal pathogens, the rice blast fungus Magnaporthe oryzae uses highly specialized infection structures called appressoria for plant penetration. Appressoria differentiated from germ tubes rely on enormous turgor pressure to directly penetrate the plant cell, in which process lipid metabolism plays a critical role. In this study, we characterized the MoPAH1 gene in M. oryzae, encoding a putative highly conserved phosphatidate phosphatase. The expression of MoPAH1 was up‐regulated during plant infection. The MoPah1 protein is expressed at all developmental and infection stages, and is localized to the cytoplasm. Disruption of MoPAH1 causes pleiotropic defects in vegetative growth, sporulation, and heat tolerance. The lipid profile is significantly altered in the Mopah1 mutant. Lipidomics assays showed that the level of phosphatidic acid (PA) was increased in the mutant, which had reduced levels of diacylglycerol and triacylglycerol. Using a PA biosensor, we showed that the increased level of PA in the Mopah1 mutant was primarily accumulated in the vacuole. The Mopah1 mutant was blocked in both conidiation and the formation of appressorium‐like structures at hyphal tips. It was nonpathogenic and failed to cause any blast lesions on rice and barley seedlings. RNA sequencing analysis revealed that MoPah1 regulates the expression of transcription factors critical for various developmental and infection‐related processes. The Mopah1 mutant was reduced in the expression and phosphorylation of Pmk1 MAP kinase and delayed in autophagy. Our study demonstrates that MoPah1 is necessary for lipid metabolism, fungal development, and pathogenicity in M. oryzae. [ABSTRACT FROM AUTHOR]

• In situ large-scale 3D visualization of membrane fouling by LSFM. • An inner concentrated DEX layer was observed in hydrophilic membrane. • Foulant distribution and penetration shown correlations with membrane fouling. Membrane fouling restricts the wide applications of membrane technology and therefore, it is essential to develop novel analytical techniques to characterize membrane fouling and to further understand the mechanism behind it. In this work, we demonstrate a capability of high-resolution large-scale 3D visualization and quantification of the foulants on/in membranes during fouling process based on light sheet fluorescence microscopy as a noninvasive reproducible optical approach. The adsorption processes of dextran (DEX) on/in two polyvinylidene fluoride membranes with similar pore structure but distinct surface hydrophilicity were clearly observed. For a hydrophilic polyvinylidene fluoride (PVDF) membrane, the diffusion and adsorption of the DEX in membrane matrix were much slower compared to that for a hydrophobic membrane. A concentrated foulant layer was observed in the superficial potion of the hydrophilic membrane matrix while the foulants were observed quickly penetrating across the overall hydrophobic PVDF membrane during a short adsorption process. Both the inner concentrated fouling layer (in membrane superficial portion) and the foulant penetration (in membrane asymmetric structure) presented correlations with membrane fouling irreversibility, which could elucidate the microscopic events of hydrophilic membrane in resisting fouling. In addition, the imaging results could be correlated with the XDLVO analysis, suggesting how the membrane-foulant and foulant-foulant interfacial interactions resulted in a time-dependent membrane fouling process. This work provides a fast, highly-sensitive and noninvasive imaging platform for in situ characterization of membrane fouling evolution and should be useful for a wide range of membrane-based process explorations. Image, graphical abstract [ABSTRACT FROM AUTHOR]