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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

基于多分支增强和融合注意力机制的水下图像增强算法

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陕西科技大学学报 2025年第1期43卷 193-202页

作者：姚斌韩典芝徐轩李婉陕西科技大学电子信息与人工智能学院陕西西安710021

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBFA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计... 详细信息

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBFA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计了青品色温修复模块和模糊恢复模块对水下图像进行色彩矫正和模糊恢复.然后,基于对多个分支特征的互补性考虑,采用循环合并策略将多个分支增强的特征利用自适应融合模块进行融合,逐步增强图像细节.最后,设计了融合注意力模块,用于深度挖掘图像在通道维度和像素维度的相关性矩阵,以提高增强图像的真实性.实验结果表明,与现有算法相比,提出的水下图像增强算法去模糊效果较好且颜色更真实,可以有效改善水下图像色偏和模糊的问题.

关键词：水下图像增强多分支增强融合注意力生成对抗网络

Control of redox potential by oxygen limitation in selective bioleaching of chalcocite and pyrite

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Rare Metals 2014年第5期33卷 622-627页

作者： Biao Wu Jian-Kang Wen bo-Wei Chen Guo-Cheng yao dian-Zuo Wang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals

Based on the bioleaching mechanism and electrochemical studies of metal sulfides, the dissolution rates of chalcocite and pyrite are controlled by redox potentials. Experiment on the bioleaching of chalcocite and pyrite under constant redox potential by sparging with nitrogen gas was demonstrated. By leaching at low and constant redox potential（〈760 mV, vs SHE）, copper recoveries of 90 %–98 % are achieved, which are 10 times more than iron recoveries. The iron-oxidizing bacterial populations are observed to continue to reduce under oxygen limitation conditions, but the Acidithiobacillus that have only sulfur-oxidizing capabilities are an attractive alternative for redox-controlled bioleaching of ***, the described redox control technique might be one of the effective approaches to balance acid and iron in Zijinshan copper bio-heap leaching practice.

关键词： Pyrite Chalcocite Bioleaching Redox potential Oxygen limitation

Microstructure and Mechanical Properties of Semi-continuous Equal-channel Angular Extruded Interstitial-free Steel

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Journal of Iron and Steel Research International 2016年第2期23卷 160-165页

作者： bo YAN Si-hai JIAO dian-hua ZHANG State Key Laboratory of Rolling and Automation Northeastern University Research and Development Center Baoshan Iron and Steel Co.Ltd.

An innovative method called semi-continuous equal channel angular extrusion （SC-ECAE） has been devel- oped to produce ullrafine grained steel by inducing severe plastic deformation. In contrast to the external forces that are exerted on specimens in traditional ECAE, the driving forces are applied on the dies in the novel SC EACE process. Commercial interslitial-free steel sheets with width of 160 mm and tbickness of 2 mm were processed re peatedly to various passes at room temperature using this method. The microstructural evolution was characterized using high-resolution electron backscatter diffraction （EBSD）, and the mechanical properties were investigated by tensile testing. The EBSD images indicated that the fraction of high angle boundaries （HABs） began to increase gradually after four passes; after six passes, elongated HAB structures with nearly submicron-scale average spacings were formed. The tensile testing results showed that strengthening was accompanied by a decrease in tensile ductili- ly, but no significant anisotropy was observed. After 10 passes, a final HAB fraction of about 90% and an overall grain size of 0.55 μm, yield strength of 638.7 MPa, an ultimate tensile strength （UTS） of 710.3 MPa, and a totfd elongation of 12.0 % were obtained.

关键词： severe plastic deformation semi-continuous equal channel angular extrusion IF steel ultrafine grainedstructure EBSD

Incidental prostate cancer in radical cystoprostatectomy specimens

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Asian Journal of Andrology 2008年第5期10卷 809-814页

作者： Xiao-Dong Jin Zhao-dian Chen bo Wang Song-Liang Cai Xiao-Lin yao Bai-Ye Jin Department of Urology The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China Department of Pathology The First Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003 China

Aim： To investigate the rates of prostate cancer （PCa） in radical cystoprostatectomy （RCP） specimens for bladder cancer in China's Mainland. To determine the follow-up outcome of patients with two concurrent cancers and identify whether prostate-specific antigen （PSA） is a useful tool for the detection of PCa prior to surgery. Methods： From January 2002 to January 2007, 264 male patients with bladder cancer underwent RCP at our center. All patients underwent digital rectal examination （DRE） and B ultrasound. Serum PSA levels were tested in 168 patients. None of the patients had any evidence of PCa before RCP. Entire prostates were embedded and sectioned at 5 mm intervals. Results： Incidental PCa was observed in 37 of 264 （14.0%） RCP specimens. Of these, 12 （32.4%） were clinically significant according to an accepted definition. The PSA levels were not significantly different between patients with PCa and those without PCa, nor between patients with significant PCa and those with insignificant PCa. Thirty-four patients with incidental PCa were followed up. During a mean follow-up period of 26 months, two patients with PSA 〉 4 ng/mL underwent castration. None of the patients died of PCa. Conclusion： The incidence of PCa in RCP specimens in China's Mainland is lower than that in most developed countries. PSA cannot identify asymptomatic PCa prior to RCP. In line with published reports, incidental PCa does not impact the prognosis of bladder cancer patients undergoing RCE

关键词： bladder cancer cystoprostatectomy incidental prostate cancer prostate-specific antigen

Model parameters estimation of aero-engine based on hybrid optimization algorithm

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航空动力学报 2011年第7期26卷 1665-1671页

作者： LI Qiu-hong LI Ye-bo JIANG dian-wen (College of Energy and Power EngineeringNanjing University of Aeronautics and Astronautics Nanjing 210016 China

A hybrid optimization algorithm for the time-domain identification of multivariable,state space model for aero-engine was presented in this *** optimization procedure runs particle swarm optimization(PSO) and least squares optimization(LSO) "in series".PSO starts from an initial population and searches for the optimum solution by updating ***,it can sometimes run into a suboptimal *** LSO can start from the suboptimal solution of PSO,and get an optimum solution by conjugate gradient *** algorithm is suitable for the high-order multivariable system which has many parameters to be estimated in wide *** optimization algorithm is applied to estimate the parameters of a 4-input 4-output state variable model(SVM) for *** simulation results demonstrate the effectiveness of the proposed algorithm.

关键词： aero-engine state variable model(SVM) particle swarm optimization(PSO) least squares optimization(LSO) hybrid optimization algorithm

Arabidopsis Transcription Factors SPL1 and SPL12 Confer Plant Thermotolerance at Reproductive Stage

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Molecular Plant 2017年第5期10卷 735-748页

作者： Lu-Men Chao yao-Qian Liu dian-Yang Chen Xue-Yi Xue Ying-bo Mao Xiao-Ya Chen National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant Sciences Shanghai Institute of Plant Physiology and Ecology University of CAS Chinese Academy of Sciences Shanghai 200032 People's Republic of China School of Life Science and Technology ShanghaiTech University Shanghai 201210 People's Republic of China plant Science Research Center Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical Garden Shanghai 201602 People's Republic of China These authors contribute equally to this article

Plant reproductive organs are vulnerable to heat, but regulation of heat-shock responses in inflorescence is largely uncharacterized. Here, we report that two of the SQUAMOSA PROMOTER BINDING PROTEIN- LIKE （SPL） transcriptional factors in Arabidopsis, SPL1 and SPL12, act redundantly in thermotolerance at the reproductive stage. The spll-1 sp112-1 inflorescences displayed hypersensitivity to heat stress, whereas overexpression of SPL 1 or SPL 12 enhanced the thermotolerance in both Arabidopsis and tobacco. RNA sequencing revealed 1939 upregulated and 1479 downregulated genes in wild-type inflorescence upon heat stress, among which one-quarter （1,040） was misregulated in spll-1 sp112-1, indicating that SPL1 and SPL12 contribute greatly to the heat-triggered transcriptional reprogramming in inflorescence. Notably, heat stress induced a large number of abscisic acid （ABA） responsive genes, of which -39% were disturbed in heat induction in spll-1 sp112-1 inflorescence. Preapplication of ABA and overex- pression of SPL1 restored the inflorescence thermotolerance in spll-1 sp112-1 and in the ABA biosynthesis mutant aba2-1, but not in the pyl sextuple mutant defective in ABA receptors PYR 1/PYL 1/PYL2/PYL4/PYL5/ PYL8. Thus, inflorescence thermotolerance conferred by SPL1 and SPL2 involves PYL-mediated ABA signaling. The molecular network consisting of SPL1 and SPL12 illustrated here shed new light on the mechanisms of plant thermotolerance at the reproductive stage.

关键词： plant thermotolerance inflorescence SPL transcription factor abscisic acid

Analysis of Sheet Curvature in Asymmetrical Cold Rolling

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Journal of Iron and Steel Research International 2013年第5期20卷 34-37页

作者： HAO Liang DI Hong-shuang GONG dian-yao State Key Laboratory of Rolling Technology and Automation Northeastern University

In asymmetric cold rolling, the workpiece is often bent downwards or upwards. A two-dimensional explicit dynamic finite element model with Arbitrary Lagrangian Eulerian （ALE） adaptive meshing technique has been employed to simulate asymmetrical sheet rolling, in which asymmetrical conditions are here due to different roll radii. To validate the simulation, the results of simulation and experiment are compared. Effects of asymmetry due to roll radii mismatch on the normal and shear distributions and on sheet curvature variations are discussed. An optimum roll radii ratio could be found to produce flat sheet. Trials were conducted to investigate the effectiveness of roll radii mismatch as an approach of sheet curvature control.

关键词： asymmetrical rolling finite element method radii ratio sheet curvature

Adaptive threading strategy based on rolling characteristics analysis in hot strip rolling

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Journal of Central South University 2017年第7期24卷 1560-1572页

作者： PENG Wen CHEN Shu-zong GONG dian-yao LIU Zi-ying ZHANG dian-hua State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Research Institute of Technology Shougang GroupBeijing 100041China

In order to improve the threading stability and the head thickness precision in tandem hot rolling process, an adaptive threading strategy was proposed. The proposed strategy was realized by the rolling characteristics analysis, and factors which affect the rolling force and the final thickness were determined and analyzed based on the influence coefficients calculation process. An objective function consisting of the influenced factors was founded, and the disturbance quantity was obtained by minimizing the function with the Nelder-Mead simplex method, and the proposed adaptive threading strategy was realized based on the calculation results. The adaptive threading strategy has been applied to one 7-stand hot tandem mill successfully, actual statistics data show that the predicted rolling force prediction in the range of +/- 5.0% is improved to 97.8%, the head thickness precision in the range of +/- 35 mu m is improved to 98.5%, and the threading stability and the head thickness precision are enhanced to a high level.

关键词： hot strip rolling adaptive threading rolling characteristics analysis influence coefficients method simplex algorithm