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Single-cell RNA sequencing facilitates the elucidation of the complete biosynthesis of the antidepressant hyperforin in St. John's wort

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Molecular Plant 2024年第9期17卷 1439-1457页

作者： Song Wu Ana Luisa Malaco Morotti Jun yang Ertao Wang Evangelos c.Tatsis National Key Laboratory of Plant Molecular Genetics CASs Center for Excellence in Molecular Plant SciencesShanghai lnstitute of Plant Physiology and EcologyChineseAcademy of SciencesShanghai 200032China University of chinese Academy of Sciences Shanghai 200032China UEPAMS-cAS-JIcs centre of Excellencefor Plant anamlcroblalSclence Snangnal 200032Cnina

Hyperforin is the compound responsible for the effectiveness of ***'s wort(Hypericum perforatum)as an antidepressant,but its complete biosynthetic pathway remains *** discovery based on co-expression analysis of bulk RNA-sequencing data or genome mining failed to discover the missing steps in hyperforin *** this study,we sequenced the 1.54-Gb tetraploid *** genome assem-bled into 32 chromosomes with the scaffold N50 value of 42.44 *** single-cell RNA sequencing,we iden-tified a type of cell,“Hyper cells”,wherein hyperforin biosynthesis de novo takes place in both the leaves and *** pathway reconstitution in yeast and tobacco,we identified and characterized four transmembrane prenyltransferases(HpPT1-4)that are localized at the plastid envelope and complete the hyperforin biosynthetic *** hyperforin polycyclic scaffold is created by a reaction cascade involving an irregular isoprenoid coupling and a tandem *** findings reveal how and where hy-perforin is biosynthesized,enabling synthetic-biology reconstitution of the complete ***,this study not only deepens our comprehension of specialized metabolism at the cellularlevel but also provides strategic guidance for elucidation of the biosynthetic pathways of other specializied metabolites in plants.

关键词： hyperforin Hypericum perforatum de novo genome sequencing single-cell RNA sequencing biosyn-thetic pathway meroterpenoids

Triple the steady-state reaction rate by decorating the In_(2)O_(3)surface with SiO_(x)for cO_(2)hydrogenation

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Journal of Energy chemistry 2024年第8期95卷 96-105,I0003页

作者： Hao Wang chun yang Xiaoyan Yu Mingrui Wang Runze yang Xiaowa Nie Ben Hang Yin Alex c.K.Yip chunshan Song Guanghui Zhang Xinwen Guo State Key Laboratory of Fine chemicals Frontier Science Center for Smart MaterialsPSU-DUT Joint Center for Energy ResearchSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina Department of chemistry the Chinese University of Hong KongHong Kong 999077China Paihau-Robinson Research Institute the MacDiarmid Institute for Advanced Materials and NanotechnologyVictoria University of WellingtonWellington 6012New Zealand Department of chemical and Process Engineering The University of CanterburyChristchurch 8041New Zealand

Indium oxide(In_(2)O_(3)),as a promising candidate for cO_(2)hydrogenation to c_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction *** on the comprehension of the dynamic evolution,this study presents an efficient strategy to alleviate the agglomeration of In_(2)O_(3)nanoparticles by the surface decoration with highly dispersed silica species(SiO_(x)).Various structural characterizations combined with density functional theory calculations demonstrated that the sintering resulted from the over-reduction,while the enhanced stability originated from the anchoring effect of highly stable In-OSi bonds,which hinders the substantial formation of metallic In(In^(0))and the subsequent agglomeration.0.6Si/In_(2)O_(3)exhibited cO_(2)conversion rate of10.0 mmol g^(-1)h^(-1)at steady state vs.3.5 mmol g^(-1)h^(-1)on In_(2)O_(3)in cO_(2)*** steady-state activity was also achieved on Pd-modified *** to the traditional Pd/In_(2)O_(3)catalyst,the methanol production rate of Pd catalyst supported on 0.6Si/In_(2)O_(3)was enhanced by 23%,showing the potential of In_(2)O_(3)modified by SiO_(x)in serving as a platform *** work provides a promising method to design new In_(2)O_(3)-based catalysts with improved activity and stability in cO_(2)hydrogenation.

关键词： cO_(2)hydrogenation In_(2)O_(3)sintering Dynamic structural evolution Surface SiO_(x)modification DFT simulations

Isomeric fluorescence sensors for wide range detection of ionizing radiations

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Defence Technology（防务技术） 2024年第4期34卷 247-257页

作者： Jimin Han Tianyu yang Li yang Yuanjian Li State Key Laboratory of Explosion Science and Technology of china Beijing Institute of TechnologyBeijing 100081China chongqing Innovation center Beijing Institute of TechnologyChongqing 401120China

In order to achieve a wider range of ionizing radiations detection,novel fluorescence sensing materials have been developed that utilize the fluorescence enhancement phenomenon caused by the intramolecular photoinduced electron transfer(PET)*** perylene diimide isomers PDI-P and PDI-B were designed and synthesized,and their molecular structures were characterized by high-resolution Fourier transform mass spectrometry(HRMS),nuclear magnetic resonance hydrogen and carbon spectroscopy(~1H and~(13)c NMR).The interaction between ionizing radiation and fluorescent molecules was simulated by Hcl *** results show that combining PDIs and Hcl can improve fluorescence through the retro-PET *** the similarities in chemical structures,the fluorescent enhancement multiple of PDI-B with aromatic amine as electron donor is much higher than that of PDI-P with alkyl *** the direct irradiation experiments of ionizing radiation,the emission enhancement multiples of PDI-P and PDI-B are 2.01 and 45.4,***,density functional theory(DFT)and time-dependent density functional theory(TDDFT)calculations indicate that the HOMO and HOMO-1 energy ranges of PDI-P and PDI-B are 0.54 e V and 1.13 e V,respectively.A wider energy range has a stronger driving force on electrons,which is conducive to fluorescence *** femtosecond transient absorption spectroscopy(fs-TAS)and transient fluorescence spectroscopy(TFS)tests show that PDI-B has shorter charge separation lifetime and higher electron transfer rate *** both isomers can significantly reduce LOD during PET process,PDI-B with aromatic amine has a wider detection range of 0.118—240 Gy due to its larger emission enhancement,which is a leap of three orders of *** breaks through the detection range of gamma radiation reported in existing studies,and provides theoretical support for the further study of sensitive and effective new materials for ionizing radiation dete

关键词： Perylene imide Intramolecular PET Ionizing radiation detection Fluorescence sensor Isomers

Study of 26 Galactic Open clusters with Extended Main-sequence Turnoffs

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Research in Astronomy and Astrophysics 2024年第6期24卷 28-37页

作者： yang-yang Deng Zhong-Mu Li Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of chinese Academy of Sciences Beijing 100049China Institute of Astronomy and Information Dali UniversityDali 671003China

Recent studies indicate that some Galactic open clusters(Ocs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(cMDs).However,the number of Galactic Ocs with eMSTO structures detected so far is limited,and the reasons for their formation are still *** work identifies 26 Galactic Ocs with undiscovered eMSTOs and investigates the causes of these *** population types and fundamental parameters of cluster samples are acquired using cMD fitting *** them,the results of 11 Ocs are reliable as the observed cMDs are *** propose the crucial role of stellar binarity and confirm the importance of stellar rotation in reproducing eMSTO *** results also show that the impact of age spread is important,as it can adequately explain the structure of young Ocs and fit the observed cMDs of intermediate-age Ocs better.

关键词： (stars:)binaries:general Galaxy:fundamental parameters (Galaxy:)open clusters and associations:general (stars:)Hertzsprung Russell and c-M-diagrams

Genomic Mosaicism of the Brain:Origin,Impact,and Utility

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Neuroscience Bulletin 2024年第6期40卷 759-776页

作者： Jared H.Graham Johannes c.M.Schlachetzki Xiaoxu yang Martin W.Breuss Department of Pediatrics Section of Clinical Genetics and MetabolismUniversity of Colorado School of MedicineAurora80045-2581COUSA Department of cellular and Molecular Medicine University of California San DiegoLa Jolla92093-0021San DiegoCAUSA Department of Neurosciences University of California San DiegoLa Jolla92093-0021San DiegoCAUSA Rady children’s Institute for Genomic Medicine San Diego92123CAUSA

Genomic mosaicism describes the phenomenon where some but not all cells within a tissue harbor unique genetic ***,research focused on the impact of genomic mosaicism on clinical phenotype—motivated by its involvement in cancers and overgrowth *** recently,we increasingly shifted towards the plethora of neutral mosaic variants that can act as recorders of cellular lineage and environmental ***,we summarize the current state of the field of genomic mosaicism research with a special emphasis on our current understanding of this phenomenon in brain development and *** the field of genomic mosaicism has a rich history,technological advances in the last decade have changed our approaches and greatly improved our *** will provide current definitions and an overview of contemporary detection approaches for genomic ***,we will discuss the impact and utility of genomic mosaicism.

关键词： Genomics Brain development Brain homeostasis Genomic mosaicism

Development in oxide metallurgy for improving the weldability of high -strength low-alloy steel-combined deoxidizers and microalloying elements

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1263-1284页

作者： Tingting Li Jian yang State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The mechanisms of oxide metallurgy include inducing the formation of intragranular acicular ferrite(IAF)using micron-sized inclusions and restricting the growth of prior austenite grains(PAGs)by nanosized particles during *** chaotically oriented IAF and refined PAGs inhibit crack initiation and propagation in the steel,resulting in high impact *** work summarizes the com-bined effect of deoxidizers and alloying elements,with the aim to provide a new perspective for the research and practice related to im-proving the impact toughness of the heat affected zone(HAZ)during the high heat input *** complex deoxidation with other strong deoxidants,such as Mg,ca,Zr,and rare earth metals(REMs),can improve the toughness of the heat-affected zone(HAZ)by re-fining PAGs or increasing IAF ***,it is difficult to identify the specific phase responsible for IAF nucleation because ef-fective inclusions formed by complex deoxidation are usually *** alloying elements,such as c,Si,Al,Nb,or cr,con-tents can impair HAZ toughness.A high c content typically increases the number of coarse carbides and decreases the potency of IAF ***,cr,or Al addition leads to the formation of undesirable *** reduces the high-temperature stability of the ***,V,and B can enhance HAZ ***-containing precipitates present good thermal *** or V(c,N)is ef-fective in promoting IAF nucleation due to its good coherent crystallographic relationship with *** formation of the B-depleted zone around the inclusion promotes IAF *** interactions between alloying elements are complex,and the effect of adding dif-ferent alloying elements remains to be *** the future,the interactions between various alloying elements and their effects on ox-ide metallurgy,as well as the calculation of the nucleation effects of effective inclusions using first principles calculations will become the focus of

关键词： oxide metallurgy technology heat affected zone high-strength low-alloy steel intragranular acicular ferrite microalloying element

comprehensive Assessment of STGSA Generated Skeletal Mechanism for the Application in Flame-Wall Interaction and Flame-Flow Interaction

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Journal of Thermal Science 2024年第5期33卷 1946-1960页

作者： YU chunkan yang Bin Institute of Technical Thermodynamics Karlsruhe Institute of TechnologyKarlsruhe 76131Germany center for combustion Energy Tsinghua UniversityBeijing 100084China

In this study,we conduct a thorough evaluation of the STGSA-generated skeletal mechanism for c_(2)H_4/*** STGSA-reduced mechanisms are taken into account,incorporating basic combustion models such as the homogeneous reactor model,one-dimensional flat premixed flame,and non-premixed counterflow ***,these models are applied to more complex combustion systems,considering factors like flame-flow interaction and flame-wall *** considerations take into account additional physical parameters and processes such as mixing frequency and *** results indicate that the skeletal mechanism adeptly captures the behavior of these complex combustion ***,it is suggested to incorporate strain rate considerations in generating the skeletal mechanism,especially when the combustion system operates under high turbulent intensity.

关键词： Species-Targeted Global Sensitivity Analysis(STGSA) mechanism reduction Partially Stirred Reactor(PaSR) spark ignition Head-on Quenching(HoQ)

Dynamic RNA methylation modifications and their regulatory role in mammalian development and diseases

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Science china(Life Sciences) 2024年第10期67卷 2084-2104页

作者： Wenlan yang Yongliang Zhao Yungui yang State Key Laboratory of Reproductive Regulation&Breeding of Grassland Livestock Inner Mongolia Key Laboratory for Molecular Regulation of the CellSchool of Life SciencesInner Mongolia UniversityHohhot 010020China cAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China china National center for Bioinformation Beijing 100101China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China Sino-Danish college University of Chinese Academy of SciencesBeijing 101408China

Among over 170 different types of chemical modifications on RNA nucleobases identified so far,RNA methylation is the major type of epitranscriptomic modifications existing on almost all types of RNAs,and has been demonstrated to participate in the entire process of RNA metabolism,including transcription,pre-mRNA alternative splicing and maturation,mRNA nucleus export,mRNA degradation and stabilization,mRNA *** to the development of high-throughput detection technologies and the identification of both dynamic regulators and recognition proteins,mechanisms of RNA methylation modification in regulating the normal development of the organism as well as various disease occurrence and developmental abnormalities upon RNA methylation dysregulation have become increasingly ***,we particularly focus on three types of RNA methylations:N^(6)-methylcytosine(m^(6)A),5-methylcytosine(m^(5)c),and N^(7)-methyladenosine(m^(7)G).We summarize the elements related to their dynamic installment and removal,specific binding proteins,and the development of high-throughput detection ***,for a comprehensive understanding of their biological significance,we also overview the latest knowledge on the underlying mechanisms and key roles of these three mRNA methylation modifications in gametogenesis,embryonic development,immune system development,as well as disease and tumor progression.

关键词： RNA methylation(m^(6)A m5c and m7G) detection techniques RNA metabolism gametogenesis embryogenesis immune system development tumorigenesis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： yang Jiang Ming cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination