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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01期 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.

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Homoclinic Solutions for a Class of Perturbed Fractional Hamiltonian Systems with Subquadratic Conditions

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1177-1196页

作者： ying LUO fei guo Yan LIU School of Mathematics Tianjin UniversityTianjin 300354P.R.China Tianjin Key Laboratory of Brain-Inspired Intelligence Technology Tianjin300354P.R.China

In this paper,we consider the following perturbed fractional Hamiltonian systems{tD_(∞)^(α)(_(-∞)D_(t)^(α)u(t))+L(t)u(t)=■_(u)W(t,u(t))+■(u)G(t,u(t)),t∈R,u∈H^(α)(R,R^(N)),whereα∈(1/2,1],L∈C(R,R^(N×N))is symmetric and not necessarily required to be positive definite,W∈C1(R×R^(N,R))is locally subquadratic and locally even near the origin,and perturbed term G∈C1(R×R^(N,R))maybe has no parity in *** the perturbed method improved by the authors,a sequence of nontrivial homo clinic solutions is obtained,which generalizes previous results.

关键词： Perturbed fractional Hamiltonian systems subquadratic condition perturbed method homoclinic solutions multiplicity

Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 64-70页

作者： guo-Fu Xu Department of Physics Shandong University

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era, building accurate intermediate-scale nonadiabatic holonomic quantum computers is clearly necessary. Given that measurements are the sole means of extracting information, they play an indispensable role in nonadiabatic holonomic quantum computers. Accordingly, developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great importance. However, while much attention has been given to the research on nonadiabatic holonomic gates, the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely lacking. In this study, we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum computers. The reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic gates. Given these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

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涤纶POY尾丝不良的原因与对策研究

合成纤维 2023年第3期52卷 19-21页

作者：王海英王国良蔡晓芬徐杰羿胜旗费国英桐昆集团浙江恒盛化纤有限公司浙江桐乡314500

尾丝的好坏是加弹过尾成功的关键性因素。总结生产实践认为尾丝不良现象和纸管长度、纸管转度与卷绕锭子转速的一致性、卷绕切换工艺和留尾时间有重要关系,有效控制这些因素,能够最大限度控制尾丝不良现象的发生,提高加弹过尾的成功率。

关键词：涤纶POY 尾丝不良卷绕切换工艺过尾成功率

Friction Characteristics of Impregnated and Non-Impregnated Graphite against Cemented Carbide under Water Lubrication

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Journal of Materials Science & Technology 2017年第10期33卷 1203-1209页

作者： Gaolong Zhang ying Liu fei guo Xiangfeng Liu Yuming Wang The State Key Laboratory of Tribology Tsinghua University Beijing 100084 China

The friction behavior of resin-impregnated and non-impregnated graphite sliding against a cemented carbide in dry, oil, and water environments using a ring–ring configuration was investigated. Friction coefficients were recorded at various speeds. The results showed that the impregnated graphite exhibited much better friction properties under water or oil lubrication than non-impregnated graphite, and the impregnated graphite could remain in the stable friction regime under high pressure × velocity（pv）.Based on scanning electron microscopy and Raman spectroscopy analyses, the different characteristics between impregnated and non-impregnated graphite were able to be attributed to the structure of the graphite and wettability of the lubricants.

关键词： Friction Resin-impregnated graphite Non-impregnated graphite Cemented carbide Water lubrication

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan YANG Zhaoyang MA Xingming guo Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

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Asking one mechanism in glial cells during neuroinflammation

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Neural Regeneration Research 2025年第4期20卷 1077-1078页

作者： Xiaoli guo Chikako Harada Takayuki Harada Visual Research Project Tokyo Metropolitan Institute of Medical ScienceTokyoJapan

Multiple sclerosis(MS),which is characterized by inflammatory demyelination in the central nervous system(CNS),is the most common neurological disease in the young adult *** autoimmune encephalomyelitis(EAE),an animal model of MS,is often used in preclinical *** data indicate that in addition to immune cells such as T cells and dendritic cells,CNS resident microglia and astrocytes play important roles in demyelinating neuroinflammation(Healy et al.,2022).In particular,microglia are key immune-competent cells that can respond to environmental *** depletion of transforming growth factor-β-activated kinase 1,a mitogen-associated protein kinase kinase kinase,in microglia is reported to reduce CNS inflammation and diminish axonal and myelin damage *** suggests that elucidating the mechanisms of microglia-specific responses during pathologies may help in the development of treatments that reduce EAE/MS disease severity(Goldmann et al.,2013).

关键词： inflammation clinical

Monogenic gene therapy for glaucoma and optic nerve injury

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Neural Regeneration Research 2025年第3期20卷 815-816页

作者： Chikako Harada Xiaoli guo Takayuki Harada Visual Research Project Tokyo Metropolitan Institute of Medical ScienceTokyoJapan

The prevalence of glaucoma, the second leading cause of global blindness, is increasing due to aging populations. In glaucoma, degeneration of the optic nerve and retinal ganglion cells(RGCs) causes visual field defec... 详细信息

关键词： visual glaucoma degeneration

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

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Neural Regeneration Research 2025年第9期20卷 2513-2519页

作者： Desmond A.Nunez Ru C.guo Division of Otolaryngology–Head&Neck Surgery Department of SurgeryFaculty of MedicineThe University of British ColumbiaVancouverBCCanada Division of Otolaryngology–Head&Neck Surgery Gordon&Leslie Diamond Health Care CentreVancouver General HospitalVancouverBCCanada Faculty of Medicine–The University of British Columbia VancouverBCCanada

Hearing loss is the third leading cause of human ***-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health ***-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing *** etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental *** stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing *** non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic *** hair cell death is a central histopathological finding in sensorineural hearing *** these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing *** EMBASE,Ovid MEDLINE,Web of Science Core Collection,and *** databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical *** red clinical trials known to the senior author we re also assessed.A total of 222studies were thus *** excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text *** resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative *** miR-34a and miR-29b levels increase with age in *** miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P GC-1α),SIRT

关键词： hearing loss hypoxia microRNAs oxidative stress sensorineural