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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： Qing-Yun Fang chengyihan Gu Yinghan chen Wencheng Yan Yong Liang Weipeng Li chengjian Zhu jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 211198China

Selective modification of peptides has always been a challenging *** selective alkylation of peptides can alter the biological activity and physical properties of molecules,and it has gained significant research *** herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis.A wide range of structurally diverse primary,secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with theα-C(sp^(3))–H in glycine residue of *** protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups.A series of relay transformations to construct cyclic peptides,to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic *** addition,mechanistic studies and density functional theory(DFT)calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET)mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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ClBBM and ClPLT2 function redundantly during both male and female gametophytes development in watermelon

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Horticultural Plant Journal 2025年第1期11卷 323-335页

作者： Qiyan Liu Dongfen Han Jinfan chen jie Wang Denghu cheng Xiner chen Jiao Jiang Shujuan Tian Jiafa Wang Man Liu Haizheng Xiong Li Yuan State Key Laboratory of Crop Stress Biology for Arid Areas College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China Department of Horticulture University of ArkansasFayettevilleAR 72701USA

As a prerequisite for sexual reproduction,gametophyte development is an interesting process involving cell proliferation,differentiation and *** has been extensively explored in model plants,but the regulatory mechanism of gametophyte development largely remains unknown in Cucurbitaceae *** present study,we have shown that watermelon ClBBM and ClPLT2,two AP2/ERF transcription factors,participated in both male and female gametophyte *** and Clplt2 single mutants resembled wild-type phenotypes in both vegetative and reproductive *** Clbbm/Clplt2 double mutant showed partial pollen abortion and bore less seeds comparing to *** results indicated that the abnormal pollen grains were caused by premature tapetum degeneration,and reduced seed-set was due to faulty embryo sac *** and ClPLT2 were expressed in FG4 embryo sacs,and their transcripts were also detectable in the tapetum and microspore of stage 9 anthers,which was consistent with developmental stages of defective phenotypes observed in double *** expression of genes essential for tapetum development,ClATM1,ClAMS,ClMS1 and ClMS188,was decreased in Clbbm/Clplt2 double ***,the transcriptome analysis indicated that ClBBM and ClPLT2 participated in tapetum and pollen wall development by regulate cell cycle,transmembrane transport,glucan and cellulose metabolic ***,ClBBM and ClPLT2 were functionally redundant in regulating gametophyte development in watermelon,and their functions differ from their homologous genes in model plant Arabidopsis.

关键词： Watermelon Gametophyte Male sterility Seedless

Controlling segregation and hardenability of gear steel based on as-cast structure

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Journal of Iron and Steel Research International 2025年第1期32卷 144-158页

作者： Hai-jie Wang Ze Zhang Peng Lan Gang chen Pu Wang Chuan-hui Jiang Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Weifang Iron and Steel Group Co. Ltd.Weifang 261000ShandongChina

Hardenability significantly impacts the distortion of gear during heat treatment,correlated to the uniformity of solute distribution in steel *** experimental analysis was conducted on the macrostructure,solute distribution,dendrite structure,and rod hardenability of 20CrMnTiH gear steel in continuously cast blooms and hot roller *** evaluation approach by the standards for the hardenability of gear steel rods and the corresponding blooms was analyzed,and the inheritance mechanism from solidification segregation to hardenability fluctuation of gear steel was *** results indicate that semi-macroscopic spot segregation located in the equiaxed zone exhibits larger size,higher solute enrichment,and worse solute homogeneity,leading to significant solute fluctuations in the blooms and hardenability fluctuation in the *** increasing the liquid steel superheat from 35 to 40℃,reducing the mold electromagnetic stirring from 300 to 100 A,and implementing the soft reduction(SR)of 7 mm at the solidification end,the equiaxed ratio of the strand decreased from 26.42%to 6.69%.Consequently,the solute fluctuation range and standard deviation decrease significantly in the transverse section,while the maximum segregation ratio,average fluctuation range,and average standard deviation of solutes C,Cr,and Mn in the spot segregation decrease at the same *** the meanwhile,the equiaxed ratio of the rod decreased from 24.89%to 4.09%,and the structure of the hardenability detection zone was transformed from equiaxed crystals to columnar ***,the solute fluctuation range and standard deviation in the transverse section decreased,while the homogeneity in spot segregation was also *** hardness difference of A and B surfaces at J9 and J15 positions was smaller than 2 HRC,meeting the qualification standard for hardenability.

关键词： Gear steel Continuous casting Solute distribution Dendritic structure Hardenability

Enhanced rate capability and cycle stability of Ti2C MXene for sodium storage through an aniline molecules welding strategy

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Tungsten 2025年第1期7卷 161-171页

作者： Hao chen Ya-Qin Wang Dong-Ting Zhang Bei Zhao min-Peng Li chen-Yang Li Tian-Peng Xu Mao-cheng Liu State Key Laboratory of Advanced Processing and Recycling of Non-Ferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology School of Computer and Communication Technology Lanzhou University of Technology

MXenes obtained significant attention in the field of energy storage devices due to their characteristic layered structure,modifiable surface functional groups,large electrochemically active surface,and regulable interlayer ***,the self-restacking and sluggish ions diffusion kinetics performance of MXenes during the alkali metal ions insertion/extraction process severely impedes their cycle stability and rate *** paper proposes an aniline molecule welding strategy for welding p-phenylenediamine（PPDA） into the interlayers of Ti2C through a dehydration condensation *** welded PPDA molecules can contribute pillar effect to the layered structure of *** pillar effect effectively maintains the structural stability during the sodium ions insertion/extraction process and effectively expands the interlayer spacing of Ti2C from 1.16 to 1.38 nm,thereby enhancing ions diffusion kinetics performance and improving the long-term cycle *** Ti2C-PPDA demonstrates outstanding Na+storage capability,exhibiting a specific capacity of 100.2 mAh·g-1at a current density of 0.1 A·g-1over 960 cycles and delivering a remarkable rate capability 81.2 mAh·g-1at a current density of 5 A·*** study demonstrates that expanding interlayer spacing is a promising strategy to enhance the Na+storage capacity and improve long-term cycling stability,which provides significant guidance for the design of two-dimensional Na+storage materials with high-rate capability and cycle stability.

关键词： Diffusion kinetics Expanding interlayer spacing Rate capability Sodium ions storage Ti2C

Effective nucleus-nucleus potentials for heavy-ion fusion reactions

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Nuclear Science and Techniques 2025年第2期36卷 103-111页

作者： Ning Wang Jin-ming chen min Liu Present Address:Department of Physics Guangxi Normal UniversityGuilin 541004China Guangxi Key Laboratory of Nuclear Physics and Technology Guilin 541004China

Based on the Skyrme energy density functional and reaction Q-value,this study proposed an effective nucleus-nucleus poten-tial for describing the capture barrier in heavy-ion fusion *** 443 extracted barrier heights were well reproduced with a root-mean-square(RMS)error of 1.53 MeV,and the RMS deviations with respect to 144 time-dependent Hartree-Fock capture barrier heights were only 1.05 *** with the Siwek-Wilczyński formula,wherein three parameters were determined by the proposed effective potentials,the measured capture cross sections at energies around the barriers were reasonably well reproduced for several fusion reactions induced by nearly spherical nuclei as well as by nuclei with large deformations,such as^(154)Sm and^(238)*** shallow capture pockets and small values of the average barrier radii resulted in the reduction of the capture cross sections for 52,54Cr-and 64 Ni-induced reactions,which were related to the synthesis of new super-heavy nuclei.

关键词： Nucleus-nucleus potential Fusion reactions Superheavy nuclei Capture cross sections

IL-17A mediates inflammation-related retinal pigment epithelial cells injury via ERK signaling pathway

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International Journal of Ophthalmology(English edition) 2025年第1期18卷 15-27页

作者： Hui-min Zhong Bing-Qiao Shen Yu-Hong chen Xiao-Huan Zhao Xiao-Xu Huang min-Wen Zhou Xiao-Dong Sun Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong UniversitySchool of MedicineShanghai 200080China National Clinical Research Center for Ophthalmic Diseases Shanghai 200080China National Clinical Research Center for Eye Diseases Shanghai 200080China Shanghai Key Laboratory of Fundus Diseases Shanghai 200080China Shanghai Engineering Center for Visual Science and Photomedicine Shanghai 200080China

AIM:To investigate whether interleukin-17A(IL-17A)gets involved in the mechanisms of inflammation-related retinal pigment epithelium(RPE)cells injury and its significance in age-related macular degeneration(AMD).MRTHODS:A sodium iodate(NaIO3)mouse model as well as IL-17A-/-mice were *** effects of inflammatory cytokines in RPE cells and retinal microglia before and after NaIO3 modeling in vivo and in vitro,were investigated using immunofluorescence,immunoprotein blotting,and quantitative real-time fluorescence polymerase chain reaction(qRT-PCR),*** using recombinant IL-17A protein(rIL-17A)or IL-17A neutralizing antibody(IL-17A NAb)were used to observe the subsequent differences in fundus,fundus photography and optical coherence tomography(OCT),cell viability,and expression of oxidative stress-related markers before and after modeling,and to screen for key signaling ***:In the scenario of NaIO3 stimulation,RPE cells obviously tended to *** proliferation and activation of retinal microglia was confirmed in NaIO3-stimulated mice,whereas such effects induced by NaIO3 were significantly ameliorated with IL-17A NAb intervention or in IL-17A-/-*** addition,IL-17A promoted the proliferation and activation of microglia as well as oxidative damage and the secretion of inflammatory cytokines alongside NaIO3-induced damage in RPE cells in vivo and ex ***,the extracellular signalregulated kinase(ERK)signaling pathway was shown to be participated in the regulation of NaIO3-induced RPE cells injury mediated by IL-17A in vivo and ex vivo,as IL-17A induced inflammatory cytokines release in the NaIO3 model was alleviated after blocking the ERK ***:IL-17A probably promotes the NaIO3-induced RPE cells injury through exacerbating inflammation in terms of retinal microglia activation and inflammatory cytokines release via ERK signaling *** of IL-17A may be a new potential ta

关键词： age-related macular degeneration retinal pigment epithelium NaIO3 microglia IL-17A

Spin freezing induced giant exchange bias in a doped Hund's metal

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 167-174页

作者： Shunjiao Li Dan Zhao Jian Li Baolei Kang min Shan Yanbing Zhou Xuyang Li Tao Wu Xianhui chen Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Superconducting Electronics(CENSE) Shanghai 200050China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Exchange bias(EB)is a fundamental phenomenon in widespread information ***,a comprehensive understanding of its microscopic origin remains a great *** key issue in the debate is the role of frustration and disorder in the EB mechanism,which motivates the exploration of the EB effect in spin glass(SG)***,in the SG state of Crdoped Hund's metal CsFe_(2)As_(2),we discover a giant EB effect with a maximum bias field of -2 T,which is almost two orders of magnitude larger than that of traditional alloy *** results indicate that the giant EB effect should originate from the exchange interactions at the natural boundaries between the tunable ferromagnetic-like(FM)regions around Cr dopants and the SG matrix,via which the FM spins are strongly pinned by the frozen spins in the SG *** addition,the temperaturedependent and cooling-field-dependent EB behaviors could be interpreted well by the SG model with frustrated FM/SG boundaries,which provides an intuitive and explicit understanding of the impact of glassy parameters on the EB *** these results suggest that the correlated metals are promising directions for exploring the EB effect in the SG state.

关键词： Hund's metal spin glass exchange bias iron-based superconductor

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Unintentional emissions of polychlorinated naphthalenes in China:Sources,composition,and historical trends

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Journal of Environmental Sciences 2025年第2期148卷 221-229页

作者： Ye Huang Lin Huang Ying Li Nazupar Sidikjan Yunshan Zhang Yan chen Yangmin chen Ye Li Wei Du Long chen YanWu Shanshan Zhang Jing Yang Wenjun Meng Guofeng Shen min Liu Shu Tao Key Laboratory of Geographic Information Science of the ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control Faculty of Environmental Science&EngineeringKunming University of Science&TechnologyKunming 650500China Laboratory of Earth Surface Processes College of Urban and Environmental SciencePeking UniversityBeijing 100871China

Polychlorinated naphthalenes(PCNs)are detrimental to human health and the *** the commercial production of PCNs banned,unintentional releases have emerged as a significant environmental ***,relevant information is still *** this study,provincial emissions for eight PCNs homologues from 37 sources in the Chinese mainland during the period of 1960-2019 were estimated based on a source-specific and time-varying emission factor *** results showed that the total PCNs emissions in 2019 reached 757.0 kg with Hebei ranked at the top among all the provinces and iron&steel industry as the biggest ***-chlorinated PCNs comprised 90%of emissions by mass,while highly chlorinated PCNs dominated in terms of toxicity,highlighting divergent priorities for mitigating emissions and safeguarding human *** emissions showed an overall upward trend from 1960 to 2019 driven by emission increase from iron&steel industry in terms of source,and from North China and East China in terms of geographic ***-capita emissions followed an inverted U-shaped environmental Kuznets curvewhile emission intensities decreased with increasing per-capita Gross Domestic Product(GDP)following a nearly linear pattern when log-transformed.

关键词： PCNs Emission inventory Emission factor Composition profile Emission intensity Chinese mainland

Achievable dual-strategy to stabilize Li-rich layered oxide interface by a one-step wet chemical reaction towards long oxygen redox reversibility

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Journal of Energy Chemistry 2025年第2期101卷 120-131页

作者： Bin He Yujie Dai Shuai Jiang Dawei chen Xilong Wang jie Song Dan Xiao Qian Zhao Yan Meng Wei Feng School of Mechanical Engineering Chengdu University Chongqing Institute of Metrology and Quality Inspection Institute of New Energy and Low-Carbon Technology Sichuan University

Oxygen release and electrolyte decomposition under high voltage endlessly exacerbate interfacial ramifications and structu ral degradation of high energy-density Li-rich layered oxide（LLO）,leading to voltage and capacity ***,the dual-strategy of Cr,B complex coating and local gradient doping is simultaneously achieved on LLO surface by a one-step wet chemical reaction at room *** functional theory（DFT） calculations prove that stable B-O and Cr-O bonds through the local gradient doping can significantly reduce the high-energy O 2p states of interfacial lattice O,which is also effective for the near-surface lattice O,thus greatly stabilizing the LLO surface,Besides,differential electrochemical mass spectrometry（DEMS） indicates that the CrxB complex coating can adequately inhibit oxygen release and prevents the migration or dissolution of transition metal ions,including allowing speedy Li+migration,The voltage and capacity fading of the modified cathode（LLO-CrB） are adequately suppressed,which are benefited from the uniformly dense cathode electrolyte interface（CEI） composed of balanced organic/inorganic ***,the specific capacity of LLO-CrB after 200 cycles at 1C is 209.3 mA h g-1（with a retention rate of 95.1%）.This dual-strategy through a one-step wet chemical reaction is expected to be applied in the design and development of other anionic redox cathode materials.

关键词： Interfacial oxygen Lithium-rich layered oxide cathode Local gradient doping One-step wet chemical reaction Surface coating