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Microorganisms play an important role in plant growth and development. In particular, endophytic fungi is one of the important kinds of microorganisms and has a mutually beneficial symbiotic relationship with host plants. Endophytic fungi have many substantial benefits to host plants, especially for woody plants, such as accelerating plant growth, enhancing stress resistance, promoting nutrient absorption, resisting pathogens and etc. However, the effects of endophytic fungi on the growth and development of woody plants have not been systematically summarized. In this review, the functions of endophytic fungi for the growth and development of woody plants have been mainly reviewed, including regulating plant growth (e.g., flowering, root elongation, etc.) by producing nutrients and plant hormones, and improving plant disease, insect resistance and heavy metal resistance by producing secondary metabolites. In addition, the diversity of endophytic fungi could improve the ability of woody plants to adapt to adverse environment. The components produced by endophytic fungi have excellent potential for the growth and development of woody plants. This review has systematically discussed the potential regulation mechanism of endophytic fungi regulating the growth and development of woody plants, it would be of great significance for the development and utilization of endophytic fungi resource from woody plants for the protection of forest resources. [ABSTRACT FROM AUTHOR]

Modern smart products are endowed with the capability to autonomously repair damage from random shocks, thereby highlighting the critical necessity to incorporate this self-healing attribute in reliability assessments. This paper investigates periodically inspected self-healing systems that are exposed to dependent competing failure processes within dynamically evolving environments. The impact of environmental changes is manifested in that both the natural degradation process and the self-healing behavior are governed by distinct laws in varying environments. Explicit formulas for the system reliability and availability are analytically derived using the stochastic process theory, and their correctness is verified by proposed simulation algorithms respectively. Meanwhile, the inspection period is optimized by minimizing the long-run average cost rate. Lastly, a practical example of semiconductor lasers is applied to showcase the application of the presented methods. The sensitivity analysis reveals that increasing the self-healing time threshold or the shock arrival rate can improve the system performance while lowering the long-run average cost rate. • Investigating self-healing systems undergoing dependent failure processes. • Exploring environmental impacts on natural degradation and self-healing behaviors. • Presenting analytical and simulation methods for system reliability indexes. • Obtaining an optimal inspection interval under periodic inspection. • Illustrating the proposed methods by a case study of semiconductor lasers. [ABSTRACT FROM AUTHOR]

• Eliminate the harmonic interference of the rolling bearing signals via the ARIMA model. • Propose a method for optimizing model parameters based on the characteristics of K-SVD algorithm. • Introduce a competitive mechanism to optimize the atomic update model at the dictionary update stage. Rolling bearings are extensively employed in industrial production as essential support components for rotating machinery. However, under conditions of high load and harsh operation, bearings are highly susceptible to failure. The weak vibration signals associated with these failures may be obscured by complex harmonic interference and strong noise, posing challenges for the accurate diagnosis of rolling bearing failures. In this paper, an autoregressive integrated moving average and competitive K-singular value decomposition (ARIMA-CK-SVD) algorithm is proposed to realize effective extraction of faulty pulse signals in a strong interference environment. First, the ARIMA model is used to preprocess the original signal to eliminate the interference of harmonic components. Second, a method is proposed for the adaptive selection of parameters in the ARIMA model, with consideration given to the characteristics of K-SVD. Subsequently, a competitive mechanism is introduced during the dictionary update phase of the algorithm to adjust the pattern of atomic updates and eliminate noise atoms. Finally, the effectiveness of the ARIMA-CK-SVD has been validated through simulation experiments and engineering tests. [ABSTRACT FROM AUTHOR]

This paper addresses the issue of the impact of the competitive behaviors of long-rental apartment firms on the rents of long-rental apartments and ordinary rental housing and introduces a dynamic gaming approach to the housing rental market domain to reveal changes in the long-term complexity of rents of long-rental apartments and ordinary rental housing caused by the competitive behavior of long-rental apartment firms. Through numerical simulation, it is found that the adoption of smaller rent adjustment strategies by firms is important for maintaining system stability, while the changes in reference effect behavior of landlords and service quality and differences in demand share have moderating effects on system stability. The enhanced reference effect of landlords, the improvement of service quality, and the increase of the difference in demand share between the two long-rental apartments help to mitigate the disruption of system stability by the increase of the adjustment factor of the firms. The decentralized long-lease apartment firms, which occupy a higher proportion of the market, are able to exert a major impact on the rent of general rental housing by taking advantage of the market, while the difference in the demand share between the two firms is the main reason for the change in the rent of long-rental apartments. [ABSTRACT FROM AUTHOR]

This study investigated the activity of the novel Aspergillus sp. R3 against rice sheath blight (RSB) fungus Rhizoctonia solani Kühn. R3 strain had strong antagonistic activity. R3 strain was Aspergillus sp. by morphological observation and molecular identification. After enrichment, separation, purification and nuclear magnetic resonance (NMR) identification of culture solution and mycelium of Aspergillus sp. R3, the main metabolite was identified as cyclopyazonic acid (CPA). We studied the effect of CPA on R. solani , including mycelial morphology, membrane permeability and lipid peroxidation. The control effect of CPA on rice seedlings infected with sheath blight was also tested. CPA inhibited the growth of R. solani in vitro and led to the atrophy of R. solani mycelia under microscopic observation. In addition, CPA exhibited antimicrobial activity against a variety of plant pathogens in vitro. With the treatment of CPA with R. solani , the malondialdehyde content and electrolyte leakage of R. solani mycelia increased compared with the control. Additionally, CPA could significantly reduced the severity of sheath blight disease of rice seedlings infected with R. solani. This is the first report of the CPA produced by Aspergillus sp. with antagonistic activity against R. solani and R. solani -induced RSB. This study indicates that Aspergillus sp. and its metabolites may serve as potential biocontrol agents against some plant pathogens. • Cyclopyazonic acid (CPA) was isolated from Aspergillus sp. R3. • CPA has stronger antimicrobial activity against Rhizoctonia solani Kühn. • CPA can effectively inhibit rice sheath blight. [ABSTRACT FROM AUTHOR]

A novel series of (1,2-benzothiazin-4-yl)acetic acid enantiomers was prepared by chiral resolution, and their absolute configurations were determined using the PGME method. The biological evaluation of the racemate and single enantiomers has shown a remarkable difference for the aldose reductase inhibitory activity and selectivity. The (R)-(−)-enantiomer exhibited the strongest aldose reductase activity with an IC50value of 0.120 μM, which was 35 times more active than the S-(+)-enantiomer. Thus, the stereocenter at the C4 position of this scaffold was shown to have a major impact on the activity and selectivity. [ABSTRACT FROM AUTHOR]

A group of novel quinoxalinone derivatives ( 4a – h ) were prepared and investigated for their inhibitory activity against ALR2 and antioxidant activity. Most of them were found to be potent aldose reductase inhibitors with IC 50 values ranging from 0.019 to 0.982 μM. The most active compound 2-(3-(4-hydroxyphenoxy)-6-fluoro-2-oxoquinoxalin-1(2 H )-yl)acetic acid ( 4c ) also had an excellent selectivity. In addition, a number of compounds showed strong antioxidant activity and the phenolic 3,5-dihydroxyl compound 4f with 7-chloro in the quinoxalinone core was most active in scavenging the DPPH radical and suppressing lipid peroxidation. [ABSTRACT FROM AUTHOR]

Quinoxalin-2(1H)-one based design and synthesisproduced several series of aldose reductase (ALR2) inhibitor candidates.In particular, phenolic structure was installed in the compounds forthe combination of antioxidant activity and strengthening the abilityto fight against diabetic complications. Most of the series 6showed potent and selective effects on ALR2 inhibition withIC50values in the range of 0.032–0.468 μM,and 2-(3-(2,4-dihydroxyphenyl)-7-fluoro-2-oxoquinoxalin-1(2H)-yl)acetic acid (6e) was the most active.More significantly, most of the series 8revealed notonly good activity in the ALR2 inhibition but also potent antioxidantactivity, and 2-(3-(3-methoxy-4-hydroxystyryl)-2-oxoquinoxalin-1(2H)-yl)acetic acid (8d) was even as strong asthe well-known antioxidant Trolox at a concentration of 100 μM,verifying the C3 p-hydroxystyryl side chain as thekey structure for alleviating oxidative stress. These results thereforesuggest an achievement of multifunctional ALR2 inhibitors having bothpotency for ALR2 inhibition and as antioxidants. [ABSTRACT FROM AUTHOR]

Abstract: A novel, non-acid series of nitroquinoxalinone derivatives was synthesized and tested for their inhibitory activity against aldose reductase as targeting enzyme. All active compounds displayed an 8-nitro group, and showed significant activity in IC50 values ranging from 1.54 to 18.17μM. Among them 6,7-dichloro-5,8-dinitro-3-phenoxyquinoxalin-2(1H)-one (7e), exhibited the strongest aldose reductase activity with an IC50 value of 1.54μM and a good SAR (structure–activity relationship) profile. [Copyright &y& Elsevier]

Green biological pretreatment of lignocellulose is the critical step in the degradation of biomass in the sustainable economy for biofuels and bio-based chemicals. In the present study, a novel laccase-producing endophytic fungus Chaetomium globosum was screened out from the flower of Hibiscus manihot L. in combination with ultrasound to improve the degradation of lignin in larch sawdust. Under the optimized conditions with the material to liquid ratio 1:20, temperature 30 °C, time 4 days, pH 7, the ultrasonic power 200 W, time 20 min, the degradation rate of lignin reached 34.29%, which increased 1.5-fold and 2-fold higher than that of fungus and ultrasonic treatment correspondingly. In addition, SEM and FTIR analysis showed that the combined treatment changed the surface morphology and chemical structure, and found that mycelium colonized in the interior of sawdust. Analysis of three types of lignin contents showed that the contents of p-Hydroxyphenyl and Guaiacyl increased from 0.46 to 0.70 mg/g and from 9.31 to 11.87 mg/g, while the contents of Syringyl propane did not change significantly, the results indicated that laccase from Chaetomium globosum might have special selectivity. After docking the three lignin monomers and laccase molecules, it was found that the hydroxyl group of Coniferyl alcohol was formed by the active groups of GLU-460 and SER-113 amino acids. The hydrogen bond distances were 1.8 Å and 2.2 Å, which were far smaller than the traditional hydrogen bond of 3.5 Å, this indicated that the compound binds strongly to the protein. The benzene ring of Sinapyl alcohol contained two methoxy groups increasing the molecular volume and hydrophobicity, which reduced laccase's ability to oxidize phenols. In general, as indicated by the results of this study, the novel endophytic fungus Chaetomium globosum from Hibiscus manihot L. has great potential to selectively degrade lignin in larch sawdust. [Display omitted] • A novel laccase-producing endophytic fungus Chaetomium globosum was screened from Hibiscus manihot L. • The optimum conditions for lignin degradation were obtained • Characteristics, structure, and contents of lignin after treatment with endophytic fungus were analyzed. • Industrial level model was developed for the lignin degradation process. [ABSTRACT FROM AUTHOR]

A series of aldose reductase (ALR2) inhibitors based on pyridothiadiazine were prepared and evaluated for their activities in ALR2 inhibition, DPPH scavenging, and MDA inhibition. Comparison studies were carried out between analogs having either hydroxyl or methoxy groups substituted on the N2-benzyl side chains of the compounds. Most of the hydroxy-substituted compounds were found to be more potent compared to their methoxy-substituted analogs with respect to DPPH inhibition (>93%) and MDA inhibition (>73%). However, ALR2 inhibitory activity was found to be affected by the electron-withdrawing substituent at the C7 position in addition to the effect of the N2-substituted benzyl group. These results provide an array of multifunctional ALR2 inhibitors possessing capacities both for ALR2 inhibition and as antioxidants. [ABSTRACT FROM AUTHOR]

Several multifunctional benzothiadiazine derivatives were synthesized and examined for their inhibition to the enzyme aldose reductase and in vitro antioxidant activity to identify novel drugs for diabetes and its complications. Most of them exhibited good inhibitory activity. Importantly, a number of compounds demonstrated strong antioxidant activity and one compound in particular was extremely active in the DPPH radical scavenging and MDA inhibition analysis. The DPPH radical scavenging rate with this compound was 98.0%, 92.3% and 42.1% at concentrations of 100 μM, 10 μM, and 1 μM, respectively, and the initial reaction rate was faster than Trolox at a concentration of 10 μM. [ABSTRACT FROM AUTHOR]

Abstract: Novel quinoxalinone derivatives were synthesized and tested for their inhibitory activity against aldose reductase. Among them, N1-acetate derivatives had significant activity in a range of IC50 values from low micromolar to submicromolar, and compound 15a bearing a C3-phenethyl side chain was identified as the most potent inhibitor with an IC50 value of 0.143 μM. The structure–activity studies suggested that both C3-phenethyl and C6-NO2 groups play an important role in enhancing the activity and selectivity of the quinoxalinone based inhibitors. [Copyright &y& Elsevier]