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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

Screening Effect in Isotropic Gaussian Processes

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Acta Mathematica Sinica,English Series 2020年第5期36卷 512-534页

作者： Jing Yu BAO fei ye ying yang Department of Mathematical Sciences Tsinghua UniversityBeijing 100062.P.R.China School of Statistics Capital University of Economics and BusinessBeijing 100026P.R.China

The screening effect is the phenomenon that optimal linear prediction of a spatial process on an unobserved location mostly depends on nearby *** is,the optimal predictor based on just nearby observations yields a good approximation of which based on the whole large ***,the approximation does not always perform well since the screening effect may not hold in all *** determine when the screening effect holds is an important issue in spatial *** paper provides some sufficient conditions for ensuring an asymptotic screening effect in Rd based on the spectral density of the underlying isotropic Gaussian process and the geometries of nearby *** results apply to isotropic processes with an arbitrary degree of *** we are predicting at origin,the conditions are(1)the spectral density is nearly a constant in balls of finite radius far from the origin,(2)the positions of nearby observations do not fall on a curve with non-zero intercept whose degree is less or equal to the order of mean square differentiability of the *** conditions are easy to verify in *** rates of the asymptotic screening effect are also *** rates depend on the rate of decrease of the spectral *** studies on the screening effect for finite samples are also provided.

关键词： Spatial statistics spectral analysis kriging screening effect

Bullous pemphigoid associated with acquired hemophilia A: A case report

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World Journal of Clinical Cases 2025年第4期13卷 28-33页

作者： Su-ye Hu Meng-Can Li Zi-Jia Hao Xu-Ya Chai Pei-Sai Li yang Liu Li-Xia Liu ying Xu Pan-Pan yang Ling-E Li Department of Dermatology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina Graduate School Hebei University of Traditional Chinese MedicineShijiazhuang 050051Hebei ProvinceChina Department of Pathology Shijiazhuang Traditional Chinese Medicine HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Acquired hemophilia A (AHA) is a rare and potentially severe bleeding disordercaused by circulating autoantibodies against factor Ⅷ (FⅧ). In approximately50% of the patients, the condition is associated with autoimmune diseases,cancers, medication use, pregnancy, and the post-partum period. Bullous pemphigoid(BP) is a chronic autoimmune subepidermal blistering disease associatedwith tissue-bound and circulating autoantibodies against BP antigens 180 (BP180)and 230 (BP230). AHA-associated BP has a high mortality rate;hence, the understandingof this disease must *** SUMMARY A 69-year-old man presented with erythema, blisters, blood blisters, and crustsaccompanied by severe pruritus for more than 20 days, and ecchymosis andswelling on his left upper arm for 3 days. Pathological examination revealed asubepidermal blister that contained eosinophils. Laboratory tests showed that theBP180 autoantibody levels had increased, isolated activated partial thromboplastintime was notably prolonged (115.6 s), and coagulation FⅧ activity wasextremely low (< 1.0%). Furthermore, the FⅧ inhibitor titer had greatlyincreased (59.2 Bethesda units). Therefore, the patient was diagnosed as having BP associated with AHA, prescribed 0.05% topical halometasone cream, and transferred to a higher-level hospitalfor effective treatment;however, he died after 2 *** AHA associated BP is rare, dangerous, and has a high mortality rate. Therefore, its timely diagnosis and effectivetreatment are necessary.

关键词： Bullous pemphigoid Acquired hemophilia A Acquired hemophilia A FactorⅧ Case report

Biooxidation-thiosulfate leaching of refractory gold concentrate

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International Journal of Minerals,Metallurgy and Materials 2020年第8期27卷 1075-1082页

作者： He-fei Zhao Hong-ying yang Lin-lin Tong Qin Zhang ye Kong Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

A process of biooxidation followed by thiosulfate leaching of gold from refractory gold concentrate was *** studies on the concentrate showed that very fine gold grains(<10μm)were encapsulated in pyrite and arsenopyrite,while the proportion of monomer gold was only 21%.The gold-bearing sample was identified as a high-sulfur fine-sized wrapped-type refractory gold *** gold leaching efficiency obtained by direct cyanidation was only 59.86%.After biooxidation pretreatment,the sulfide minerals were almost completely decomposed,92 wt%of the mineral particles of the biooxidation residue were decreased to<38μm,and the proportion of monomer gold in the biooxidation residue was over 86%.Meanwhile,the gold content in the biooxidation residue was enriched to 55.60 g/t,and the S,Fe,and As contents were reduced to approximately 19.8 wt%,6.97 wt%,and 0.13 wt%,*** thiosulfate was used for gold extraction from the biooxidation residue of the refractory gold *** results showed that the optimal reagent conditions were 0.18 M thiosulfate,0.02 M copper(II),1.0 M ammonia,and 0.24 M *** these conditions,a maximum gold leaching efficiency of 85.05%was obtained.

关键词： thiosulfate leaching gold biooxidation refractory gold concentrate process mineralogy

A distribution-free test of independence based on a modified mean variance index

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Statistical Theory and Related Fields 2023年第3期7卷 235-259页

作者： Weidong Ma fei ye Jingsong Xiao ying yang Department of Mathematical Sciences Tsinghua UniversityBeijingPeople’s Republic of China School of Statistics Capital University o fEconomics and BusinessBeijingPeople’s Republic of China

Cui and Zhong(2019),(Computational Statistics&Data Analysis,139,117–133)proposed a test based on the mean variance(MV)index to test independence between a categorical random variable Y with R categories and a continuous random variable *** ingeniously proved the asymptotic normality of the MV test statistic when R diverges to infinity,which brings many merits to the MV test,including making it more convenient for independence testing when R is *** paper considers a new test called the integral Pearson chi-square(IPC)test,whose test statistic can be viewed as a modified MV test statistic.A central limit theorem of the martin-gale difference is used to show that the asymptotic null distribution of the standardized IPC test statistic when R is diverging is also a normal distribution,rendering the IPC test sharing many merits with the MV *** an application of such a theoretical finding,the IPC test is extended to test independence between continuous random *** finite sample performance of the proposed test is assessed by Monte Carlo simulations,and a real data example is presented for illustration.

关键词： Test of independence asymptotic null distribution mean variance index k-sample Anderson Darling test statistic concentration type inequality

Convenient Synthesis of Two Novel Oxazolidines and Primary Research on their Biological Activities

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Chinese Chemical Letters 2006年第7期17卷 891-894页

作者： ying Jiao LI fei ye College of Science Northeast Agricultural University Harbin 150030

Two novel N-dichloroacetyl oxazolidines were synthesized with a simple, mild and convenient method in good yields. The compounds were Characterized by IR, 1^H NMR and elemental analysis. The preliminary biological tes... 详细信息

关键词： Herbicide safener oxazolidines biological activity.

Sedimentary geochemical proxies for methane seepage at Site C14 in the Qiongdongnan Basin in the northern South China Sea

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Acta Oceanologica Sinica 2019年第7期38卷 84-95页

作者： Tiantian Sun Daidai Wu fei yang Lihua Liu Xuegang Chen ying ye Ocean College of Zhejiang University Zhoushan 316021China Key Laboratory of Gas Hydrate Guangzhou Institute of Energy ConversionChinese Academy of SciencesGuangzhou 510640China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Pilot National Laboratory for Marine Sciences and Technology(Qingdao)Qingdao 266071China

Recent studies have shown that specific geochemical characteristics of sediments can be used to reconstruct past methane seepage *** this work,the correlation between the Sr/Ca and Mg/Ca ratios of sediment samples is analyzed and the sulfate concentration profile in Site C14 from cold-seep sediments in the Qiongdongnan Basin in northern South China Sea is *** results confirmed that,sulfate at 0–247 cm below sea floor(Unit I)is mainly consumed by organic matter sulfate reduction(OSR),while sulfate at 247–655 cm(UnitⅡ)is consumed by both the OSR and the anaerobic oxidation of methane(AOM).In addition,the bottom sediment layer is affected by weak methane *** Mo and U enrichment factors also exhibit similar trends in their respective depth *** responses of trace elements,including Co/Al,Ni/Al,Cr/Al and Zn/Al ratios to methane seepage allowed the study of depositional conditions and methane seepage *** on the results,it is speculated that the depositional conditions of UnitⅡchanged with depth from moderate conditions of sulfidic and oxic conditions to locally anoxic conditions,and finally to suboxic conditions due to methane fluid *** stable isotope values of chromium-reducible sulfide produced by AOM and those of sulfide formed by OSR in the early diagenetic environment suffered serious depletion of *** was probably due to weak methane leakage,which caused the slower upward diffusion and the effect of early diagenesis on the *** is necessary to consider the effects of depositional environments and diagenesis on these geochemical parameters.

关键词： Qiongdongnan Basin trace elements stable isotope values anaerobic oxidation of methane methane activity

Dynamical characteristic of measurement uncertainty under Heisenberg spin models with Dzyaloshinskii-Moriya interactions

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Frontiers of physics 2019年第3期14卷 123-131页

作者： ying-Yue yang Wen-yang Sun Wei-Nan Shi fei Ming Dong Wang Liu ye School of Physics & Material Science Anhui University Hefei 230601 China CAS Key Laboratory of Quantum Information University of Science and Technology of China Hefei 230026 China

The dynamics of measurement's uncertainty via entropy for a one-dimensional Heisenberg XYZ mode is examined in the presence of an inhomogeneous magnetic field and Dzyaloshinskii-Moriya (DM) interaction. It shows that the uncertainty of interest is intensively in connection with the filed's temperature, the direction-oriented coupling strengths and the magnetic field. It turns out that the stronger coupling strengths and the smaller magnetic field would induce the smaller measurement's uncertainty of interest within the current spin model. Interestingly, we reveal that the evolution of the uncertainty exhibits quite different dynamical behaviors in antiferromagnetic (Ji> 0) and ferromagnetic (Ji< 0) frames. Besides, an analytical solution related to the systematic entanglement (i.e., concurrence) is also derived in such a scenario. Furthermore, it is found that the DM-interaction is desirably working to diminish the magnitude of the measurement's uncertainty in the region of high-temperature. Finally, we remarkably offer a result ful strategy to govern the ent ropy-based uncertainty through utilizing quantum weak measurements, being of fundamentally importance to quantum measurement estimation in the context of solid-state-based quantum information processing and comp ut at ion.

关键词： measurement uncertainty concurrence Heisenberg XYZ chain weak measurement lower bound

Numerical study on flow fields and aerodynamics of tilt rotor aircraft in conversion mode based on embedded grid and actuator model

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Chinese Journal of Aeronautics 2015年第1期28卷 93-102页

作者： Zhang ying ye Liang yang Shuo Aviation Key Laboratory of Science and Technology on Aerodynamics of High Speed and High Reynolds Number AVIC Aerodynamics Research Institute

A method combining rotor actuator disk model and embedded grid technique is presented in this paper, aimed at predicting the flow fields and aerodynamic characteristics of tilt rotor aircraft in conversion mode more efficiently and effectively. In this method, rotor＇s influence is considered in terms of the momentum it impacts to the fluid around it; transformation matrixes among different coordinate systems are deduced to extend actuator method＇s utility to conversion mode flow fields＇ calculation. Meanwhile, an embedded grid system is designed, in which grids generated around fuselage and actuator disk are regarded as background grid and minor grid respectively, and a new method is presented for ‘donor searching＇ and ‘hole cutting＇ during grid assembling. Based on the above methods, flow fields of tilt rotor aircraft in conversion mode are simulated, with threedimensional Navier–Stokes equations discretized by a second-order upwind finite-volume scheme and an implicit lower–upper symmetric Gauss–Seidel（LU-SGS） time-stepping scheme. Numerical results demonstrate that the proposed CFD method is very effective in simulating the conversion mode flow fields of tilt rotor aircraft.

关键词： actuator aircraft rotor searching assembling symmetric coordinate donor stepping Stokes