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Streptomyces species are known for their ability to efficiently produce secondary metabolites, including various antibiotics. Wuyiencin, an antibiotic produced by Streptomyces albulus CK15, is commonly used in agriculture to control fungal diseases in crops and vegetables. In this study, we utilized atmospheric and room temperature plasma (ARTP) mutagenesis to generate mutant S. albulus strains with improved fermentation capabilities for wuyiencin production. After mutagenizing the wild-type S. albulus CK15 strain once and conducting two rounds of antimicrobial screening, three genetically stable mutants (M19, M26, and M28) were identified. These mutants showed increased wuyiencin production by 17.4%, 13.6%, and 18.5% in comparison to the CK15 strain in flask culture, respectively. The M28 mutant exhibited the highest wuyiencin activity, producing 1443.0 ± 134.6 U/mL in flask culture and 1673.8 ± 127.4 U/mL in a 5 L fermenter. These results demonstrate that ARTP is an efficient tool for microbial mutation breeding and improving wuyiencin production. [ABSTRACT FROM AUTHOR]

(1) Background: An increasing amount of research has supported the role of radiomics for predicting pathological complete response (pCR) to neoadjuvant chemoradiation treatment (nCRT) in order to provide better management of locally advanced rectal cancer (LARC) patients. However, the lack of validation from prospective trials has hindered the clinical adoption of such studies. The purpose of this study is to validate a radiomics model for pCR assessment in a prospective trial to provide informative insight into radiomics validation. (2) Methods: This study involved a retrospective cohort of 147 consecutive patients for the development/validation of a radiomics model, and a prospective cohort of 77 patients from two institutions to test its generalization. The model was constructed using T2-weighted, diffusion-weighted, and dynamic contrast-enhanced MRI to understand the associations with pCR. The consistency of physicians' evaluations and agreement on pathological complete response prediction were also evaluated, with and without the aid of the radiomics model. (3) Results: The radiomics model outperformed both physicians' visual assessments in the prospective test cohort, with an area under the curve (AUC) of 0.84 (95% confidence interval of 0.70–0.94). With the aid of the radiomics model, a junior physician could achieve comparable performance as a senior oncologist. (4) Conclusion: We have built and validated a radiomics model with pretreatment MRI for pCR prediction of LARC patients undergoing nCRT. [ABSTRACT FROM AUTHOR]

Severe infection with multidrug-resistant Enterobacterales caused by the plasmid-induced colistin resistance gene MCR-1 is a serious public health challenge. In this case, it is necessary and pressing to find a treatment to overcome antibiotic resistance. Here, we investigated the synergistic effect and mechanism of loperamide combined with colistin against MCR-1-positive pathogens. We evaluated the combined effect of loperamide and colistin using the checkerboard method and the time-kill experiment. The results showed that loperamide could enhance the bactericidal ability of colistin, and this combination regimen could completely kill the tested bacteria within 4 h. Subsequently, spectrofluorimetric methods were used to explore the mechanism of loperamide combined with colistin. The results indicated that the mode of action of loperamide combined with colistin was found to involve mechanical disruption of the membrane. Furthermore, molecular simulation and microscale thermophoresis results revealed that loperamide reduced the impact of MCR-1 protein by directly binding to its active site. In addition, the combined regimen of loperamide and colistin effectively reduced the bacterial load in the thighs of mice while increasing the protection rate by 70%. In short, as a potential lead compound, loperamide can enhance the killing effect of colistin on pathogenic Enterobacterales carrying MCR-1 by causing membrane damage and inhibiting MCR-1 protein activity. [ABSTRACT FROM AUTHOR]

In this article, a novel unit motor mathematical model (UMMM) of segmented long primary double-sided linear induction motor (LP-DSLIM) is established and a cooperative control strategy for segmented LP-DSLIM fed by one inverter is proposed. First, the conventional UMMM is theoretically analyzed. Then, a virtual secondary is introduced aiming at accurately describing the secondary current when secondary passes through the primary segments. To acquire the secondary and primary flux linkage with different coupling lengths, the secondary resistance, secondary inductance, and mutual inductance are modified by using the coupling factor. According to the established UMMM, a cooperative control strategy for segmented LP-DSLIM fed by one inverter is developed. It is that the d-axis of the synchronous dq coordinate system is oriented to the total secondary flux linkage, the d-axis and q-axis components of the weighted primary current control the total secondary flux linkage and thrust. The effectiveness of the proposed UMMM and cooperative control strategy is validated by simulation and experiment. [ABSTRACT FROM AUTHOR]

Purpose: No data on predicting the survival of AML patients based on the level of trace elements in the serum have been presented to date. The aims of this prospective cohort study were as follows: (i) to evaluate the serum Cu and Zn levels in people from Northeast China, (ii) to assess the association between the serum Cu level (SCL) and Cu to Zn ratio (SCZR) and clinical and nutrition data, and (iii) to investigate the predictive values of the SCL and SCZR in newly diagnosed de novo AML patients. Methods: A total of 105 newly diagnosed AML patients and 82 healthy controls were recruited. The serum Cu and Zn levels were determined by inductively coupled plasma spectrometry. The associations of SCL and SCZR with the survival of these AML patients were assessed by Cox proportional hazards models. Results: Both SCL and SCZR were positively related to the blast percentage of bone marrow and C-reactive protein, negatively related to albumin level and CEBPA double mutation and were significantly associated with worse overall survival and disease-free survival. Meanwhile, patients with higher SCL had worse CTCAE levels, and patients with higher SCZR showed less complete remission during the first course of induction chemotherapy. Moreover, higher SCZR was positively associated with ELN risk stratification, and was negatively associated with haemoglobin level and prognostic nutritional index (PNI). Conclusion: The SCL and SCZR are associated with long-term survival in patients with newly diagnosed AML undergoing intensive induction and may serve as important predictive biomarkers. [ABSTRACT FROM AUTHOR]

Disseminated Rhizomucor pusillus infection is a very rare but fatal complication in immunocompromised patients, because of aggressive clinical process with delayed diagnosis by routine laboratory tests. Recently, cell-free DNA next-generation sequencing (cfDNA NGS) has been used for the timely detection of infectious pathogens including mucormycosis. Herein, we described an 18-year-old male with Philadelphia-like acute lymphoblastic leukemia who received a timely diagnosis of R. pusillus infection by cell-free DNA next-generation sequencing, and confirmed by silver staining and qPCR on biopsy tissue. To the best of our knowledge, this was the first case of disseminated R. pusillus infection detected by cfDNA NGS and confirmed by histology in an adult leukemia patient. In addition, this case was supposed to be the most extensive R. pusillus infection diagnosed, involving the lung, skin, liver, kidney, spleen and brain, and the only one case who survived the infection had a favorable outcome through treatment with liposome amphotericin B sequential posaconazole. This case suggested that cfDNA NGS could be used to successfully detect rare pathogen infections, and this was especially important for R. pusillus because timely diagnosis and effective treatment could improve the prognosis of this kind of patient. [ABSTRACT FROM AUTHOR]

Pulse density modulation (PDM) is often applied in inductively coupled power transfer (ICPT) systems to improve high-frequency inverter (HFI) efficiency. However, the PDM may cause the inverter output current fluctuation, even interruption for light load or low-quality factor system. This may result in the difficulty for the implementation of soft switching in ICPT. In this article, an improved PDM (IPDM) strategy is proposed by optimizing the distribution of switch sequences. Through the current fluctuation numerical analysis and Fourier decomposition, IPDM can reduce the current fluctuation and improve the system efficiency. The experimental results on a 20 kW ICPT system prototype show that the proposed IPDM strategy reduces the HFI output current ripple coefficient is 40% to 65% lower than PDM, and the efficiency is also improved. [ABSTRACT FROM AUTHOR]

Efficiency is very important in inductively coupled power transfer (ICPT) systems. To maintain a high efficiency, a maximum efficiency tracking (MET) method based on parameter detection is proposed in the paper. The basic idea is to convert the load value to the active short-circuit (ASC) time interval for the semi-controlled rectifier on the pick-up side. The ASC time interval and the transmitting coil current are detected to calculate the load and mutual inductance values on the transmitting side. According to the detected parameters, the output voltage of the high-frequency inverter that makes the system run at its maximum efficiency can be calculated and controlled. In addition, the load voltage is controlled by the high-frequency rectifier on the pick-up side. Simulation and experimental results show that this method can quickly achieve MET without wireless communication. Furthermore, the difference between the experimental maximum efficiency and the theoretical maximum efficiency is no more than 2%. [ABSTRACT FROM AUTHOR]

To improve the efficiency of high frequency inverter (HFI) in inductively coupled power transfer system, pulse density modulation (PDM) is often used. However, the output current of the HFI fluctuates seriously, especially at light load. It affects the stable operation of the system and the implementation of zero voltage switching. In this article, an improved pulse density modulation (IPDM) is proposed to reduce current fluctuation. It applies harmonics pulse to replace the fundamental pulse and zero state, and evenly distributes the switching sequence to reduce current fluctuation. Simultaneously, the best phase-shift angle of harmonics is obtained by using the transient analysis method to further reduce the output current fluctuation. The IPDM current fluctuation is less than PDM and the efficiency become higher at light load by the theoretical analysis, while PDM is better at heavy load. So, a hybrid modulation strategy is applied that IPDM and PDM are used for light and heavy load, respectively. The experimental results show that the HFI output current ripple coefficient is reduced by 15% to 62% and the efficiency is improved at light load. [ABSTRACT FROM AUTHOR]

Grey mould is caused by the ascomycetes Botrytis cinerea in a range of crop hosts. As a biological control agent, the nucleoside antibiotic wuyiencin has been industrially produced and widely used as an effective fungicide. To elucidate the effects of wuyiencin on the transcriptional regulation in B. cinerea, we, for the first time, report a genome-wide transcriptomic analysis of B. cinerea treated with wuyiencin. 2067 genes were differentially expressed, of them, 886 and 1181 genes were significantly upregulated and downregulated, respectively. Functional categorization indicated that transcript levels of genes involved in amino acid metabolism and those encoding putative secreted proteins were altered in response to wuyiencin treatment. Moreover, the expression of genes involved in protein synthesis and energy metabolism (oxidative phosphorylation) and of those encoding ATP-binding cassette transporters was markedly upregulated, whereas that of genes participating in DNA replication, cell cycle, and stress response was downregulated. Furthermore, wuyiencin resulted in mycelial malformation and negatively influenced cell growth rate and conidial yield in B. cinerea. Our results suggest that this nucleoside antibiotic regulates all aspects of cell growth and differentiation in B. cinerea. To summarize, some new candidate pathways and target genes that may related to the protective and antagonistic mechanisms in B. cinerea were identified underlying the action of biological control agents. [ABSTRACT FROM AUTHOR]

The parameter identification of the inductively coupled power transfer (ICPT) system is of great significance for the high performance control, efficiency optimization and safe operation of the system. A method realizing mutual inductance and load identification without affecting load operation is proposed in this paper. Two inverters and two matching transformers are applied in transmitting side. One is called main inverter operating in resonant state and another is called auxiliary inverter in non resonant state. Two matching transformers are connected in series. The operating state of the system can be divided into mode 1 and mode 2 according to the non-operation or operation of the auxiliary inverter. Theoretical derivation shows that the transmitting coil current peak is enveloped when system operates in mode 2. Then the mutual inductance and load parameter can be determined according to the maximum and minimum values of the envelope. By designing the operating frequency of the auxiliary inverter and its current, the load voltage of mode 2 is basically the same as that of mode 1. The identification of mutual inductance and load are carried out under different condition. The results show that proposed method of the mutual inductance and load identification is feasible without affecting the load operation and the identification errors of mutual inductance and load are less than 6%. [ABSTRACT FROM AUTHOR]

Background: Grey mould is an important plant disease worldwide, caused by Botrytis cinerea, resulting in serious economic loss. Wuyiencin, a low toxicity, high efficiency, and broad-spectrum agricultural antibiotic, has been demonstrated effectiveness against B. cinerea. Results: Wuyiencin treatment inhibited growth and sporulation of B. cinerea, specifically altering hypha morphology and intracellular structures. These changes were accompanied by differential expression (fold change > 2.0) of 316 proteins identified by iTRAQ-labelling LC-MS/MS analysis (P < 0.05). Up-regulation of 14 proteins, including carbohydrate metabolism proteins and cell wall stabilization proteins, was validated by parallel reaction monitoring (PRM). Down-regulation of 13 proteins was validated by PRM, including regulators of energy metabolism, nucleotide/protein synthesis, and the biosynthesis of mediators of plant stress and decay. Conclusion: Our results confirm the inhibitory biological effects of wuyiencin on B. cinereal and elaborate on the differentially expressed proteins and associated pathways implicated in the capacity of wuyiencin to debilitate the growth and pathogenicity of grey mould. This study provides validated candidates for further targeted exploration with the goal of optimizing wuyiencin as a safe, low-toxicity agent for biological control. [ABSTRACT FROM AUTHOR]

Deadbeat predictive current control (DPCC) is an effective model-based motor control method. However, due to the unbalanced inductance and parameter variations of the segmented powered linear motor stator, the conventional model of linear motors is not accurate, which ultimately affect the performance of the control. This paper proposes a novel DPCC based on the recursive least squares (RLS) method to identify the parameters of the dual three-phase segmented powered linear motor (SP-LM) model. First, the influence of unbalanced inductance caused by the segmented motor stator and parameter variations of the conventional DPCC are analyzed. Second, a discrete RLS model of the dual three-phase SP-LM is established, which is a common model for both linear induction motors (LIMs) and linear synchronous motors (LSMs). Finally, the model parameters are identified by the RLS method and the deadbeat principle is used to predict the current. The proposed method effectively eliminates the influence of unbalanced inductance and the parameter variation, improves the current control performance and reduces the thrust fluctuation. Experiments based on hardware-in-the-loop verify the proposed method. [ABSTRACT FROM AUTHOR]

To predict the neoadjuvant chemoradiation therapy (CRT) response in patients with locally advanced rectal cancer (LARC) using radiomics and deep learning based on pre-treatment MRI and a mid-radiation follow-up MRI taken 3–4 weeks after the start of CRT. A total of 51 patients were included, 45 with pre-treatment, 41 with mid-radiation therapy (RT), and 35 with both MRI sets. The multi-parametric MRI protocol included T2, diffusion weighted imaging (DWI) with b-values of 0 and 800 s/mm2, and dynamic-contrast-enhanced (DCE) MRI. After completing CRT and surgery, the specimen was examined to determine the pathological response based on the tumor regression grade. The tumor ROI was manually drawn on the post-contrast image and mapped to other sequences. The total tumor volume and mean apparent diffusion coefficient (ADC) were measured. Radiomics using GLCM texture and histogram parameters, and deep learning using a convolutional neural network (CNN), were performed to differentiate pathologic complete response (pCR) vs. non-pCR, and good response (GR) vs. non-GR. Tumor volume decreased and ADC increased significantly in the mid-RT MRI compared to the pre-treatment MRI. For predicting pCR vs. non-pCR, combining ROI and radiomics features achieved an AUC of 0.80 for pre-treatment, 0.82 for mid-RT, and 0.86 for both MRI together. For predicting GR vs. non-GR, the AUC was 0.91 for pre-treatment, 0.92 for mid-RT, and 0.93 for both MRI together. In deep learning using CNN, combining pre-treatment and mid-RT MRI achieved a higher accuracy compared to using either dataset alone, with AUC of 0.83 for predicting pCR vs. non-pCR. Radiomics based on pre-treatment and early follow-up multi-parametric MRI in LARC patients receiving CRT could extract comprehensive quantitative information to predict final pathologic response. [ABSTRACT FROM AUTHOR]

Due to the dynamic longitudinal end effect, the motor flux is lagging and the thrust is fluctuated in a long-primary double-sided linear induction motor (DSLIM). In this paper, a thrust fluctuation reduction method is proposed for the DSLIM with segmented power supply. The mathematical model of the DSLIM module considering the dynamic longitudinal end effect is established first, and a new field orientation is presented by solving variation of the motor flux when the secondary enters or leaves a motor module. Then, the thrust expression is deduced based on the new field orientation, and a coefficient is proposed to present the thrust bias in a single module. The restraint of the thrust bias is implemented by increasing or changing the slip frequency according to the orientation in the movement. The proposed coefficient and the thrust control method are validated by simulation and experiment results. [ABSTRACT FROM AUTHOR]

This paper proposes an improved pulse density modulation (IPDM) power control method for semi-bridgeless active rectifier (SBAR) in inductive power transfer (IPT) system. In this method, the input voltage pulse sequences of the SBAR can be distributed more evenly compared with the traditional PDM, so the output voltage ripple can be reduced effectively. Besides, for multiple paralleled pickups, the interleaved IPDM is developed to further suppress the output voltage ripple. In addition, the characteristics of zero-voltage switching and zero current-switching for the SBAR's switches can also be achieved in the proposed IPDM method by synchronization control for the gate signals of the SBARs. The experimental results on a 30 kW IPT prototype with four paralleled pickups verified the proposed method. [ABSTRACT FROM AUTHOR]

Biocontrol approach, using beneficial microorganisms, is becoming an important alternative to the use of chemical fungicides to control crop diseases. Therefore there is a need to found new effective biocontrol agents. Herein, a bacterial strain named NKZ-259 was isolated from soil samples obtained from Qilian Mountain, Qinghai, using the dilution plate method and streak plate technique. Strain NKZ-259 was identified as Streptomyces roseoflavus based on 16S rDNA sequencing, which displayed high antagonistic activity against six fungal pathogens tested. A greenhouse experiment showed that the use of NKZ-259 fermentation broth reduced the incidence of the tomato gray mold by 66.67%, and promoted the growth of tomato and pepper seedlings, with a significant increase in plant height, root length, and fresh weight compared to controls; the field experiment also showed the growth promotion of tomato and pepper seedlings by the use of NKZ-259 fermentation broth. Furthermore, indoleacetic acid (IAA) production was also detected in strain NKZ-259 using the Salkowski’s reagent method, and was important for its plant growth-promoting effects. The results suggest that NKZ-259 has potential for commercial application as a biofertilizer or biocontrol agent. [ABSTRACT FROM AUTHOR]

Inductive power transfer is used to transfer energy across a relatively large air gap by electric resonance. The power supply region of primary coils along the track is segmented with gaps to minimize the capacity of the high-frequency inverters by reducing the loss of uncoupled region, and the several sets of secondary coils are installed aboard in the rail transit application. In this paper, the equivalent impedances of segmented primary coils, which will change when secondary coils run through the gaps between primary coils, are derived. The characteristics of resonant frequencies are obtained according to the derived equivalent impedances of primary coils. A resonant frequency tracking control method, in which the switching frequencies of inverters are modulated according to the measured curves of the resonant frequencies of the primary coil, is proposed to realize the primary resonance at all times while the secondary coil is running. Finally, the effectiveness of the proposed method is experimentally verified. [ABSTRACT FROM AUTHOR]

Subtilisin-like proteases are widely distributed and reported to be required for virulence in pathogenic fungi. In chestnut blight fungus Cryphonectria parasitica, prb1, encoding a putative subtilisin-like protease, was expressed and recombinant Prb1 protein was shown to have a protease activity in vitro. prb1-deleted mutants exhibited reduced total protease activity by 60%. The Δ prb1 mutants showed a phenotype of reduced aerial hyphae, lower level of sporulation, and a significant reduction in virulence. Additionally, site-directed mutagenesis of Prb1 protein revealed that D195, H227, and S393 are critical for C. parasitica Prb1 function in vivo. Transcriptional analysis showed that deletion of prb1 also reduced the transcript accumulation levels for genes encoding key components of the heterotrimeric G-protein signaling pathway, including cpga1, cpgb1, cpgc1, and ste12. Furthermore, deletion of prb1 results in the accumulation of autophagic bodies in the fungus. Taken together, our results showed that prb1-encoded protease functions in the regulation of virulence, phenotypical traits, and autophagy in C. parasitica. [ABSTRACT FROM AUTHOR]

It is a key issue for inductively coupled power transfer system that the output power is regulated with high efficiency especially over a wide load range. In this paper, a novel harmonic-based phase-shifted control method is proposed. With this method, the harmonic component other than the fundamental component of the resonant inverter output voltage is employed to regulate the transferred power. The output power is controlled by changing the phase-shifted angle of the inverter. Different from the conventional approaches, the switching frequency in this method is much lower than the resonant frequency, meaning much reduced switching losses. The operation principle, switching strategy, and dead-time effect have all been presented. Experimental results demonstrate that the proposed power control method can achieve significant performance improvement at the light-load condition. [ABSTRACT FROM AUTHOR]

To improve the control performance of unbalanced load of parallel-connected dual induction motors fed by a single inverter, a novel control strategy based on the weighted vector control is proposed. In this paper, a weighted flux linkage vector model of dual induction motors is developed, and then the control expressions of weighted rotor flux linkage and summation torque of dual speed-irrelevant motors are derived. The weight value of vector control for dual induction motors in unbalanced load is distributed automatically according to the torques and motor speeds. The experimental results in multiple induction motor platforms prove that the proposed method can start in a wide load range, especially at heavy unbalanced load and improves the performance of dynamic response with a sudden change of unbalanced load. [ABSTRACT FROM AUTHOR]

Abstract: Furnace sorbent injection (FSI) is used to remove SO2 formed during coal combustion by injecting sorbent into the high temperature zone of a furnace above the fireball. FSI is cost effective for older coal-fired boilers, especially when space or capital budgets are limited. To optimize the design and performance of FSI, an SO2/sorbent modeling scheme that simultaneously considers calcination (or dehydration), sintering, and sulfation has been developed and implemented. It is coupled with a three-dimensional combustion model based on computational fluid dynamics to determine the most desirable locations for sorbent injection and to optimize the amount of sorbent needed to achieve a targeted SO2 removal efficiency. A sensitivity analysis was conducted to determine the effect of flue gas temperature, particle diameter, and SO2 concentration on the extent of sulfation. This SO2/sorbent sub-model was applied to a 126-MW front-wall fired boiler firing eastern bituminous coal. The SO2 removal efficiencies predicted by the model agreed well with those measured in the field. The modeling results indicated that sorbent injected directly into the furnace through boosted over-fired air ports is more effective at removing SO2, due to longer residence time and better mixing, relative to ports higher in the furnace with poor mixing. This modeling approach is optimized for full-furnace application to facilitate the design process. [ABSTRACT FROM AUTHOR]

Abstract: A numerical model based on computational fluid dynamics (CFD) was developed and validated to simulate the performance of a catalytic monolith reformer for the production of hydrogen that could be used in fuel cell systems. The whole reactor was modeled as porous media for the process of autothermal reforming with n-hexadecane feed. CFD results provided an adequate match to experimental data from literature with respect to temperature and the mole fractions of H2, CO2 and CO products. The percentage difference between each experimental measurement of the mole fraction of hydrogen and the corresponding CFD prediction was less than 16.8%. It was found that the thermal conductivity of the solid catalyst substrate affected the temperature profile in the reactor, but its effect on product hydrogen concentration was negligible. The calculated reforming efficiency based on hydrogen decreased by 11.8% as power input was increased from 1.7 to 8.4kW. [Copyright &y& Elsevier]

Abstract: Steam reforming of iso-octane in a monolithic type reactor was simulated by a three-dimensional computational fluid dynamics model. The variations of hydrogen production and reactor temperature along the length of the reactor were calculated at isothermal, adiabatic and constant heat flux conditions. The reaction rate expressions based on steam reforming of methane in the Langmuir-Hinshelwood format were used to model steam reforming of iso-octane. The difference between the simulated results and experimental data on hydrogen produced was less than 18%. The results indicated that a large drop in temperature was in the first one-tenth of the reactor under adiabatic conditions with inlet temperatures of 600–900°C. To achieve the same mole fraction of hydrogen (0.27, dry basis) at the exit of the reactor, the maximum temperature difference across the reactor was much smaller at certain heat flux conditions than that at adiabatic conditions. Further, rate of hydrogen production may be evenly distributed in the reactor under certain conditions of constant heat flux. [Copyright &y& Elsevier]

Abstract: Jet fuel reforming was analyzed for both partial oxidation and autothermal reforming processes based on the chemical-reaction equilibria with possible use of solid oxide fuel cells in the auxiliary power units of aircraft to reduce pollutant emissions. Parameters considered in this paper were the oxygen-to-carbon ratio (0–0.7), the steam-to-carbon ratio (0–1), and the reformer temperature (500–). The product compositions and energy change of the reforming process were calculated for 12 hydrocarbons of a surrogate jet fuel under the isothermal conditions and the jet fuel under the adiabatic conditions. Solid carbon in the form of graphite was included as one of the products. The effect of 12 hydrocarbons on the oxygen-to-carbon ratio at the carbon formation boundary was negligible above . Under isothermal conditions, the maximum yield of hydrogen, carbon monoxide, or syngas was at the carbon formation boundary. Under adiabatic conditions, the minimum required oxygen-to-carbon ratio to avoid carbon formation was decreased from 0.52 to 0.38 and the corresponding temperature was reduced from 844 to with the increase of steam-to-carbon ratio from 0 to 1 for the jet fuel reforming. The maximum reforming efficiency based on the synthesis gas was about 83% for the considered steam-to-carbon ratios. [Copyright &y& Elsevier]

Abstract: Gas-particle flow in three cyclones was numerically modeled using the Eulerian–Lagrangian approach. A tangential lift-off boundary condition was developed and included in the CFD simulations of cyclone performance via a user-defined function. Particles were considered as detached from the surface if they met the criterion of tangential lift-off; otherwise they were captured by the surface. Prediction of the collection efficiency in cyclones was conducted using the three different boundary conditions: (1) bottom trap only; (2) cone and bottom trap; and (3) the tangential lift-off, which is a combination of trap and reflect. Comparison with experimental data in literature indicates that the tangential lift-off boundary condition yields more accurate predictions than other boundary conditions. [Copyright &y& Elsevier]

In this article, a hardware-assisted real-time simulation phase-domain (PD) model of a dual three-phase segmented powered linear permanent magnet synchronous machine (SP-LPMSM) used in electromagnetic drive is established. The model is able to consider the end-effect, saturation effect, coupling effect, and open-phase fault conditions, which are specially occurs in the segmented structure in SP-LPMSM. The unbalanced inductances and saturation effect caused by the segmented structure are investigated and a simplified look-up table for inductances is introduced. Additionally, to accurately evaluate the coupling effect, the permanent magnet (PM) flux linkage is decoupled into the product of unit PM flux linkage and coupling coefficient. In order to avoid the numerical impulse caused by the derivative in the progress of calculating back-EMF, sigmoid function is adopted to express the coupling coefficient. Meanwhile, to make the PD-model compatible with the open-circuit fault conditions, incidence matrices and current constraint matrices are introduced to unify the PD-models with different winding connection types and open circuit faults into one general form. The PD-model realized in field-programmable gate arrays (FPGA) based hardware is validated in comparison with finite-element analysis results. [ABSTRACT FROM AUTHOR]

MnO2-CeO2/PG-FA catalysts were prepared by supporting MnO2-CeO2 to PG-FA and used to remove Hg0 in simulated flue gas. The results show that MnO2-CeO2/PG-FA catalyst had excellent and stable Hg0 removal activity, which was mainly due to the combination effect of the catalytic oxidation activity by MnO2-CeO2 and the adsorption ability by PG-FA. Mn8-Ce0.5/PG-FA (with 8.0% MnO2 and 0.5% CeO2 loading) catalyst showed the highest Hg0 removal efficiency at 140 °C and Hg0 removal efficiency could be maintained above 95% with the space velocity of 6000 h−1 and Hg0 concentration of 160 μg/m3. O2 promoted Hg0 removal by MnO2-CeO2/PG-FA catalyst, while SO2 and H2O had inhibitory effects. In the presence of O2, the inhibitory effect of SO2 and H2O can be obviously weakened. MnO2-CeO2/PG-FA catalysts were characterized with scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption experiments (TPD). The results of SEM and XRD showed that the active components MnO2-CeO2 dispersed well on the surface of PG-FA support. The results of XPS and TPD show that the Hg0 removal process over MnO2-CeO2/PG-FA catalyst included adsorption and oxidation, HgO and HgSO4 were generated and adsorbed on the catalyst. MnO2-CeO2/PG-FA catalyst also showed excellent regeneration performance after Hg0 removal. [ABSTRACT FROM AUTHOR]

In propulsion systems requiring high speed and high acceleration, the long primary high-temperature superconducting linear synchronous machine (HTS-LSM) is a competitive candidate, since it can provide steady and high thrust. However, the armature windings on the long primary uncovered by a mover with HTS magnets can cause large flux leakage, which can lead to a high armature reaction voltage and a poor power factor. In this paper, to restrain the armature reaction voltage of the long primary HTS-LSM, compensation windings are proposed for installation on the primary. First, a mathematical model of a five-phase four-pole long primary HTS-LSM is established, and it is determined that the high armature reaction voltage is caused by the large self-inductance of uncovered armature windings. Then, compensation winding is applied in the armature winding to reduce the equivalent self-inductance. Four different compensation winding installation positions are studied and compared. To prevent the current in the compensation windings from affecting the function of the HTS-racetrack magnet on the mover, a switch control strategy for the compensation windings is proposed. Finally, prototypes of armature windings with compensation windings are manufactured and the effectiveness of the compensation windings are validated and compared. [ABSTRACT FROM AUTHOR]

Sparse Bayesian learning (SBL) with its self-regulation and uncertainty estimation features, has become a popular topic in the field of sparse signal recovery. However, it is a challenging problem to employ zero-norm penalty on signals in the hierarchical framework of SBL. In this paper, an SBL approach that approximates the zero-norm penalized spare signal recovery is proposed based on the idea that signals can be modeled using generalized Gaussian distribution (GGDs). It should be noted that the mean and variance of GGDs are related to its shape parameters, making the direct use of GGDs in Bayesian inference impractical. To solve this problem, we derives a proposition and further build a new hierarchical Bayesian framework (HrBayFw). The proposed HrBayFw is equivalent to assign ℓ p -norm penalty to signals, and the parameter p can be designed to approximate 0. Thus, the zero-norm penalized spare signal recovery can be realized using SBL, and the use of the proposition enables tractable marginalization over all parameters. The main advantage of the proposed approach is that it achieves a lower reconstruction error than current Bayesian methods. Numerical simulations evidence that the proposed SBL approach achieves better accuracy performance in terms of normalized-mean-square-error comparing with other contemporary algorithms. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study was to examine the molecular epidemiology and clinical characteristics of HMPV infection among children with ARIs in Nanjing. Methods: The respiratory samples were collected from 2078 children (≤ 14 years) with acute respiratory infections and were tested for HMPV using real-time RT-PCR. Amplification and sequencing of the HMPV G gene were followed by phylogenetic analysis using MEGA 7.0. Result: The detection rate of HMPV among children was 4.7% (97/2078), with a concentration in those under 5 years of age. Notably, the peak season for HMPV prevalence was observed in winter. Among the 97 HMPV-positive samples, 51.5% (50/97) were available for characterization of the HMPV G protein gene. Phylogenetic analysis indicated that the sequenced HMPV strains were classified into three sublineages: A2c111nt − dup (84.0%), B1 (2.0%), and B2 (14.0%). Conclusion: There was an incidence of HMPV among hospitalized children during 2021–2022 in Nanjing with A2c111nt − dup being the dominant strain. This study demonstrated the molecular epidemiological characteristics of HMPV among children with respiratory infections in Nanjing, China. [ABSTRACT FROM AUTHOR]

Grey mould caused by Botrytis cinerea is a devastating disease responsible for large losses to agricultural production, and B. cinerea is a necrotrophic model fungal plant pathogen. Membrane proteins are important targets of fungicides and hotspots in the research and development of fungicide products. Wuyiencin affects the permeability and pathogenicity of B. cinerea, parallel reaction monitoring revealed the association of membrane protein Bcsdr2, and the bacteriostatic mechanism of wuyiencin was elucidated. In the present work, we generated and characterised ΔBcsdr2 deletion and complemented mutant B. cinerea strains. The ΔBcsdr2 deletion mutants exhibited biofilm loss and dissolution, and their functional activity was illustrated by reduced necrotic colonisation on strawberry and grape fruits. Targeted deletion of Bcsdr2 also blocked several phenotypic defects in aspects of mycelial growth, conidiation and virulence. All phenotypic defects were restored by targeted gene complementation. The roles of Bcsdr2 in biofilms and pathogenicity were also supported by quantitative real-time RT-PCR results showing that phosphatidylserine decarboxylase synthesis gene Bcpsd and chitin synthase gene BcCHSVII were downregulated in the early stages of infection for the ΔBcsdr2 strain. The results suggest that Bcsdr2 plays important roles in regulating various cellular processes in B. cinerea. Key points: • The mechanism of wuyiencin inhibits B. cinerea is closely associated with membrane proteins. • Wuyiencin can downregulate the expression of the membrane protein Bcsdr2 in B. cinerea. • Bcsdr2 is involved in regulating B. cinerea virulence, growth and development. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) have raised numerous concerns in recent years as emerging environmental contaminants. At present, research on environmental contamination by antibiotics focuses on medical, animal husbandry, and aquaculture fields, with few studies on environmental contamination by agricultural antibiotics in the field of plant protection. Wuyiencin is a low toxicity, high efficiency, and broad-spectrum agricultural antibiotic. It has been widely used in agricultural production and it effectively controls crop fungal diseases. In the present study, pot experiments with four soil treatments (A, B, C and D) were set up in a greenhouse to investigate the effect of the application of wuyiencin on the fate of typical ARGs and microbial community. Eight typical ARGs were detected by real-time PCR and the microbial communities were analyzed using high-throughput sequencing. The results showed that wuyiencin neither significantly influenced ARG abundance and absolute gene copy numbers, nor significantly varied microbial community among treatments. Since it only was short-term results, and the detection number of ARGs was limited, whether wuyiencin is safe or not to ecological environment when using for long-term will need further deep research. [ABSTRACT FROM AUTHOR]

The performance of voice-based Parkinson's disease (PD) detection systems degrades when there is an acoustic mismatch between training and operating conditions caused mainly by degradation in test signals. In this paper, we address this mismatch by considering three types of degradation commonly encountered in remote voice analysis, namely background noise, reverberation and nonlinear distortion, and investigate how these degradations influence the performance of a PD detection system. Given that the specific degradation is known, we explore the effectiveness of a variety of enhancement algorithms in compensating this mismatch and improving the PD detection accuracy. Then, we propose two approaches to automatically control the quality of recordings by identifying the presence and type of short-term and long-term degradations and protocol violations in voice signals. Finally, we experiment with using the proposed quality control methods to inform the choice of enhancement algorithm. Experimental results using the voice recordings of the mPower mobile PD data set under different degradation conditions show the effectiveness of the quality control approaches in selecting an appropriate enhancement method and, consequently, in improving the PD detection accuracy. This study is a step towards the development of a remote PD detection system capable of operating in unseen acoustic environments. • Acoustic mismatch degrades the performance of voice-based PD detection systems. • Automatic quality control can identify the presence and type of degradations in signals. • Identifying degradations can inform the choice of an optimal enhancement method. • Appropriate enhancement algorithms can effectively compensate the acoustic mismatch. [ABSTRACT FROM AUTHOR]

This work focuses on studying the oscillating length scale of gas pipeline leakage flame restricted by parallel sidewalls with various separation distances. A series of experiments are conducted with 3, 6 and 10 mm nozzles and propane is used as fuel. Results show that reduction of the sidewall separation distance hinders the air entrainment, and provokes significant enlargement of the oscillation amplitude. Besides, the oscillating length scale of propane jet fire is also found to increase with the fuel flow rate. Finally, a new physical model, based on the scaling analysis of the fuel flow field and previous work, is proposed to characterize the variation of oscillating length for the restricted propane jet fire. The results obtained in this work and in previous studies, correlate with a better agreement using the present model than a previous suggested model. This work is not only a significant supplement to the flame oscillation instability physics from previous results for the flame restricted by parallel sidewalls, but also can provide some scientific basis to the design and management on the gas fuel energy storage and transportation systems in the cities to reduce the possible fire thread to the surrounding buildings. [ABSTRACT FROM AUTHOR]

A method for minimising the L1 norm relying on the convex combination of two affine projection sign algorithms is proposed. The major drawbacks of the affine projection sign type algorithms are a poor convergence rate and instability in time‐variant scenarios, especially in the presence of abrupt changes. A convex combination method is used to obtain a superior performance. Instead of minimising the squared error in the conventional convex combination theory, the minimisation of the L1 norm is introduced to offer a more robust solution in the presence of a non‐Gaussian impulsive interference. The good performances in terms of the convergence rate and the steady‐state error are demonstrated in a plant identification experiment that includes the impulsive noise and abrupt changes. [ABSTRACT FROM AUTHOR]

Various physical characteristics, including ultrasonic waves, active acoustic emissions, vibrations, and thermal imaging, have been used for blade fault detection. In this work, we propose using the sound produced by spinning wind blades to identify faults. To the best of our knowledge, passive acoustic information has not yet been explored for this task. In particular, we develop three networks targeting different scenarios. The main contributions of this work are threefold. First, when normal and aberrant data are available for supervised learning, an attention-convolutional recurrent neural network is designed to show the feasibility of using passive sound information to conduct fault detection. Second, in the absence of abnormal training data, we build a normal-encoder network to learn the distributions of normal data through semisupervised learning, which avoids the requirement of abnormal training data. Third, when multiple devices are used to collect the data, due to different properties of devices, there is a domain mismatch issue. To overcome this, we create an adversarial domain adaptive network to close the gap between the source and target domains. Acoustic signal datasets of actual wind turbine operations are collected to evaluate our fault detection systems. The findings demonstrate that the proposed systems offer high classification accuracy and indicate the feasibility of passive acoustic signal-based wind turbine blade fault detection with one step close to automatic detection. [ABSTRACT FROM AUTHOR]

In this paper, a normalized least mean square (NLMS) adaptive filtering algorithm based on the arctangent cost function that improves the robustness against impulsive interference is proposed. Owing to the excellent characteristics of the arctangent cost function, the adaptive update of the weight vector stops automatically in the presence of impulsive interference. Thus, this eliminates the likelihood of updating the weight vector based on wrong information resulting from the impulsive interference. When the priori error is small, the NLMS algorithm based on the arctangent cost function operates as the conventional NLMS algorithm. Simulation results show that the proposed algorithm can achieve better performance than the traditional NLMS algorithm, the normalized least logarithmic absolute difference algorithm and the normalized sign algorithm in system identification experiments that include impulsive interference and abrupt changes. [ABSTRACT FROM AUTHOR]

To reduce the combustion temperature of diesel soot, the Fe−Ce composite oxide catalysts with varying composition supported by three‐dimensional nickel foams were prepared by hydrothermal reaction and impregnation method. The internal structure and performance of the monolithic catalysts were characterized by X‐ray diffraction, Raman, scanning electron microscope, X‐ray photoelectron spectroscopy and catalyst activity evaluation techniques. The results revealed that when the molar ratio of Ce and Fe was 0.5, the CeO2/Fe2O3@NF catalyst showed the best catalytic activity of soot oxidation, good stability and water resistance. Besides, the addition of NO and H2O was helpful to improve the catalytic performance for soot oxidation, when 10 % H2O and 800 ppm NO were mixed into 20 %O2/N2 atmosphere, the T10, T50 and T90 values could decrease to 299 °C, 344 °C and 389 °C, respectively. [ABSTRACT FROM AUTHOR]

Streptomyces albulus CK-15 produces various secondary metabolites, including the antibiotics wuyiencin and toyocamycin, which can reportedly control a broad range of plant fungal diseases. The production of these nucleoside antibiotics in CK-15 is regulated by two biosynthesis gene clusters. To investigate the potential effect of toyocamycin biosynthesis on wuyiencin production, we herein generated S. albulus strains in which a key gene in the toyocamycin biosynthesis gene cluster, namely toyF, was either deleted or overexpressed. The toyF deletion mutant ∆toyF did not produce toyocamycin, while the production of wuyiencin increased by 23.06% in comparison with that in the wild-type (WT) strain. In addition, ΔtoyF reached the highest production level of wuyiencin 4 h faster than the WT strain (60 h vs. and 64 h). Further, toyocamycin production by the toyF overexpression strain was two-fold higher than by the WT strain, while wuyiencin production was reduced by 29.10%. qRT-PCR showed that most genes in the toyocamycin biosynthesis gene cluster were expressed at lower levels in ∆toyF as compared with those in the WT strain, while the expression levels of genes in the wuyiencin biosynthesis gene cluster were upregulated. Finally, the growth rate of ∆toyF was much faster than that of the WT strain when cultured on solid or liquid medium. Based on our findings, we report that in industrial fermentation processes, ∆toyF has the potential to increase the production of wuyiencin and reduce the timeframe of fermentation. [ABSTRACT FROM AUTHOR]

S-adenosylhomocysteine ( SAH), formed after donation of the methyl group of S-adenosylmethionine ( SAM) to a methyl acceptor, is reversibly hydrolyzed to adenosine ( ADO) and homocysteine ( HCY) by S-adenosylhomocysteine hydrolase ( SAHH). In chestnut blight fungus ( Cryphonectria parasitica), sahh, a hypovirus-regulated gene that encodes a deduced SAHH protein was shown to have an SAHH enzymatic activity in vitro. Deletion of sahh resulted in the increased accumulation of intracellular SAH and SAM but decreased ADO, and a remarkably increased accumulation of transcripts that encode adenosine kinase, methionine adenosyltransferase, and an O-methyltransferase, key components of the methylation pathway. The Δ sahh knockout mutants showed a phenotype of slower growth rate, fewer aerial hyphae, loss of orange pigment, absence of asexual fruiting bodies and conidia, and a significant reduction in virulence. Deletion of sahh significantly reduced the accumulation level of transcripts of the cyp1 that encodes cyclophilin A as well as genes of the heterotrimeric G-protein signaling pathways including cpga1, cpgb1, and cpgc1 and ste12, a target activated by the MAP kinase cascade. Taken together, we demonstrated that SAHH is required for virulence and multiple traits of phenotype in C. parasitica, by regulation of the expression of genes involved in key process of the cell. [ABSTRACT FROM AUTHOR]

A controlled-PM Maglev system with permanent magnets and electromagnets excitation together can improve the lift/weight ratios, and reduce electromagnetic power consumption at the same air gap compared with a conventional electromagnetic attractive levitation system. It has been proved to be a very effective approach with great potential for application in magnetic levitation system. This paper analyses the magnetic force characteristics of linear synchronous motor in a controlled-PM maglev model vehicle system in our lab with finite element method (FEM), presents the relationship between the magnetic forces and air gap at different current excitation, thrust-angle performance, and experiment results. [ABSTRACT FROM AUTHOR]

Antibody-drug conjugates (ADCs) have arisen as a promising class of biotherapeutics for targeted cancer treatment, combining the specificity of monoclonal antibodies with the cytotoxicity of small-molecule drugs. The choice of an appropriate payload is crucial for the success development of ADCs, as it determines the therapeutic efficacy and safety profile. This review focuses on payloads derived from natural products, including cytotoxic agents, DNA-damaging agents, and immunomodulators. These offer several advantages such as diverse chemical structures, unique mechanism of actions, and potential for improved therapeutic index. Challenges and opportunities associated with their development were highlighted. This review underscores the significance of natural product payloads in the elaboration of ADCs, which serves as a valuable resource for researchers involved in developing and optimizing next-generation ADCs for cancer treatment. [Display omitted] • A comprehensive overview of payloads originating from natural products for ADCs is systematically presented. • The evolutionary history and mechanism of action of representative natural-based payloads are underscored. • Succinct discussions on challenges and prospects are included to inform the future design of natural-based payloads. [ABSTRACT FROM AUTHOR]

• Investigated the impact of impervious surface disconnection at catchment scale. • Infiltration of RPA affects the effect of impervious surface disconnection most. • Impervious surface disconnection may cause higher peak flows. • Increase the depression storage of RPA can reduce runoff in case of low infiltration. As urbanization continues to advance, the increase in impervious surfaces, especially effective impervious areas (EIA), has resulted in a decrease in infiltration and an increase in surface runoff. Due to the direct impact of EIA on the urban hydrologic cycle, reducing the EIA by redirecting the runoff from the paved surfaces to the receiving pervious area (RPA) is an effective measure for restoring the health of the urban hydrologic cycle. Previous studies have primarily focused on EIA disconnections at the plot scale; however, due to the high heterogeneity of surfaces and the complexity of overland flow paths at the catchment scale, the impact of EIA disconnection on urban hydrographs remains uncertain. In this study, we aimed to evaluate the hydrological response of EIA disconnection by routing runoff from EIA to RPA using the Storm Water Management Model (SWMM) at the catchment scale. Multiple scenarios of factors, including rainfall under different return periods, three EIA disconnection scenarios, three infiltration scenarios, three antecedent soil moisture (ASM) scenarios, and three depression storage of RPA scenarios were considered, and the SWMM was utilized to simulate the hydrological response of EIA disconnection. The results showed that EIA disconnection had a positive effect on runoff control for return periods of less than a 5-yr period, but the effect gradually decreased as return periods exceeded a 5-yr period. Among the various influencing factors, RPA infiltration had the most significant impact on hydrological response. With the high infiltration scenarios, the maximum reduction ratios of peak flow and runoff depth were 28.1 % and 43.9 % when the return period was less than 5-yr, respectively. When the return periods were greater than 5-yr, the maximum reduction ratios of peak flow and runoff depth were 13.6 % and 24.7 %, respectively. With the extremely low infiltration scenarios, there was little variation in the peak flow and runoff depth reduction in different return periods, with maximum values of 2.5 % and 1.9 %, respectively, and the peak flow even increased in the 50-yr and 100-yr return periods after EIA disconnection. Consequently, when the infiltration of RPA was low, it was difficult to reduce peak flow under high return periods by relying solely on the infiltration of RPA. Nevertheless, as the depression storage capacity of RPA was increased, the runoff control effect improved, and the peak flow and runoff depth could still be reduced by 39.0 % and 49.2 %, respectively, even under the condition of a 100-yr return period. This study provides new insights into the impact of EIA disconnection on the hydrologic cycle and offers effective strategies for urban stormwater control and management at the catchment scale. [ABSTRACT FROM AUTHOR]

The experimentally known split (3 + 2) five‐electron donor bicyclo[3.2.1]octa‐2,6‐dien‐4‐yl (bcod) ligand provides a flexible alternative to the rigid planar cyclopentadienyl (Cp) ligand. In this connection, the structures and energetics of the binuclear iron carbonyl complexes (bcod)2Fe2(CO)n (n = 4, 3, 2, 1) have been investigated by density functional theory for comparison with the corresponding Cp2Fe2(CO)n derivatives. The cis and trans doubly CO‐bridged (bcod)2Fe2(μ‐CO)2(CO)2 structures are the lowest energy tetracarbonyl structures, similar to the Cp2Fe2(CO)4 system. However, an unbridged (bcod)2Fe2(CO)4 isomer lies only ~1 kcal/mol in energy above the doubly bridged isomers. The flexibility of the bcod ligand leads to low‐energy singlet and triplet spin state structures with agostic hydrogen atoms for the unsaturated (bcod)2Fe2(CO)n (n = 3, 2, 1) systems. Analogous structures are not found in the corresponding Cp2Fe2(CO)n systems with the rigid Cp ligand. Such structures, effectively involving donation of an electron pair from an olefinic C‐H bond to an iron atom through three‐center two‐electron C‐H‐Fe bonding, are energetically competitive with isomeric structures with metal‐metal multiple bonds. [ABSTRACT FROM AUTHOR]

• Retrospective study on recurrence after R0 resection in patients with DCCA. • Patients with LN metastasis have poorer LRFS and OS compared to LN-negative patients. • Locoregional recurrence is the main cause of postoperative failure. • Novel strategies are needed to improve local control. This study aimed to determine the prognostic factors and generate an atlas of a distribution of locoregional recurrence (LRR) in patients with distal cholangiocarcinoma (DCCA), after pancreatoduodenectomy (PD) without adjuvant radiotherapy. 124 DCCA cases registered in our institutional database from 2006 to 2018 were analyzed retrospectively. The Cox proportional hazards model was used for multivariable analysis. All recurrence sites were centrally reviewed, and LRRs were plotted on one CT scan of a template that represents the relapse pattern of the patients. The median follow-up time was 35.3 months (95% CI 22.1–48.5 months). Independent prognostic factor for locoregional recurrence-free survival was lymph node metastasis (p = 0.014). Older age, pancreas invasion, and lymph node metastasis were associated with poor survival (both p < 0.05). During the follow-up period, 69 patients (55.6%) developed disease progression. Among them, 45 patients (65.2%) had recurrence in the locoregional components. 21 patients (30.4%) were diagnosed with liver metastasis. Of the patients with LRR, most recurrences occurred in the nodes along the superior mesenteric artery (36.2%), nodes around the abdominal aorta (26.1%), nodes in the hepatoduodenal ligament (13.0%), nodes around the celiac artery (10.1%), and anastomotic stoma (10.1%). The high-risk sites of LRR after PD for primary DCCA are the nodes along the superior mesenteric artery, abdominal aorta, nodes in the hepatoduodenal ligament, nodes around the celiac artery, and anastomotic stoma. Adjuvant radiation should cover these areas to improve locoregional control for these patients. [ABSTRACT FROM AUTHOR]

Microbial antagonists and their bioactive metabolites provide one of the best alternatives to chemical pesticides to control crop disease for sustainable agriculture and global food security. The rice endophyte Streptomyces hygroscopicus OsiSh-2, with remarkable antagonistic activity towards the rice blast fungus Magnaporthe oryzae , was reported in our previous study. The present study deciphered the possible direct interaction mode of OsiSh-2 against M. oryzae. An in vitro antibiotic assay for OsiSh-2 culture filtrate revealed strong suppression of mycelial growth, conidial germination and appressorial formation of M. oryzae. Meanwhile, severe morphological and internal abnormalities in M. oryzae hyphae were observed under a scanning electron microscope and transmission electron microscope. Foliar treatment of rice seedlings by OsiSh-2 culture filtrate in the greenhouse and in the field showed 23.5% and 28.3% disease reduction, respectively. Correspondingly, OsiSh-2 culture filtrate could induce disorganized chitin deposition in the cell wall and lowered ergosterol content in the cell membrane of M. oryzae. Additionally, cell wall integrity pathway activation, large cell electrolytes release, reactive oxygen species accumulation and tricarboxylic acid cycle-related enzyme activity changes were found in M. oryzae. All these results suggested that the direct antagonistic activity of OsiSh-2 against M. oryzae may be attributed to damaging the integrity of the cell wall and membrane and disrupting mitochondrial function in the pathogen. Unlabelled Image • Endophytic Streptomyces suppressed the rice blast disease efficiently in the field and in the greenhouse. • Endophytic Streptomyces inhibited M. oryzae growth, conidial germination and appressorial formation. • Endophytic Streptomyces damaged the integrity of M. oryzae cell wall and membrane. • Endophytic Streptomyces induced fungal ROS burst and affected mitochondrial dehydrogenase activities in M. oryzae. [ABSTRACT FROM AUTHOR]