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Chinese Physics B 2024年第7期33卷 419-428页

作者： jackson Pame Lenin SShagolsem Department of Physics National Institute of Technology ManipurImphalIndia

We study the effect of particle size polydispersity(δ) on the melting transition(T*), local ordering, solid–liquid coexistence phase and dynamics of two-dimensional Lennard–Jones fluids up to moderate polydispersity by means of computer simulations. The particle sizes are drawn at random from the Gaussian(G) and uniform(U) distribution *** these systems, we further consider two different kinds of particles, viz., particles having the same mass irrespective of size, and in the other case the mass of the particle scales with its size. It is observed that with increasing polydispersity,the value of T*initially increases due to improved packing efficiency(φ) followed by a decrease and terminates at δ ≈8%(U-system) and 14%(G-system) with no significant difference for both mass types. The interesting observation is that the particular value at which φ drops suddenly coincides with the peak of the heat capacity(CP) curve, indicating a transition. The quantification of local particle ordering through the hexatic order parameter(Q_6), Voronoi construction and pair correlation function reveals that the ordering decreases with increasing δ and T. Furthermore, the solid–liquid coexistence region for the G-system is shown to be comparatively wider in the T –δ plane phase diagram than that for the U system. Finally, the study of dynamics reveals that polydisperse systems relax faster compared to monodisperse systems;however, no significant qualitative differences, depending on the distribution type and mass polydispersity, are observed.

关键词： polydispersity ordering phase diagram dynamics

The influence of various grease compositions and silver nanoparticle additives on electrically induced rolling-element bearing damage

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Friction 2024年第4期12卷 796-811页

作者： Samuel BOND Robert L.jackson German MILLS Department of Chemistry and Biochemistry Auburn UniversityAuburn 36849-5412USA Department of Mechanical Engineering Auburn UniversityAuburn 36849-5412USA

Leakage currents accelerate surface degradation of metal contacts via small scale arcing across lubricating films,but recent observations suggest that metallic nanoparticle additives in lubricants may be useful to improve contact *** findings prompted a study that examined electrically induced surface pitting of steel contacts in the presence of several lubricating greases including some containing nanometer-sized colloidal silver(Ag)*** rolling sphere-on-disk experiments were conducted under electro-tribological loads employing polyurea greases derived from mineral and synthetic base oils with and without *** forces and electrical resistance were monitored continuously during the tests;surface changes were characterized by means of optical spectroscopy,stylus profilometry,and scanning electron microscopy(SEM)including compositional analysis using energy dispersive spectroscopy(EDS).The observations demonstrate that surface pitting induced by arcing occurs mainly at the points were the rolling motion changes direction and that eroded metal is deposited along the wear ***-sized pits are formed which contain carbon and oxygen indicating that arcing causes decomposition of the hydrocarbon *** findings indicate a significant inhibition of pitting is induced by the Ag nanoparticles;some greases containing other additives exhibit a similar,although less pronounced,effect.

关键词： electric motor bearings wheel bearings electric vehicles arcing electrically induced bearing damage pitting leakage current stray current

Cultivating potential:Harnessing plant stem cells for agricultural crop improvement

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Molecular Plant 2024年第1期17卷 50-74页

作者： Penelope Lindsay Kyle W.Swentowsky David jackson Cold Spring Harbor Laboratory Cold Spring HarborNY 11724USA National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhanHubei430070China

Meristems are stem cell-containing structures that produce all plant organs and are therefore important targets for crop *** regulators control the balance and rate of cell divisions within the *** these regulators impacts meristem architecture and,as a consequence,plant *** this review,we discuss genes involved in regulating the shoot apical meristem,inflorescence meristem,axillary meristem,root apical meristem,and vascular cambium in *** highlight several examples showing how crop breeders have manipulated developmental regulators to modify meristem growth and alter crop traits such as inflorescence size and branching *** transformation techniques are another innovation related to plant meristem research because they make crop genome engineering *** discuss recent advances on plant transformation made possible by studying genes controlling meristem ***,we conclude with discussions about how meristem research can contribute to crop improvement in the coming decades.

关键词： meristem crop improvement plant transformation plant breeding crop yield gene editing

Reactive oxygen species promote endurance exercise-induced adaptations in skeletal muscles

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Journal of Sport and Health Science 2024年第6期13卷 780-792页

作者： Scott K.Powers Zsolt Radak Li Li Ji Malcolm jackson Department of Applied Physiology University of FloridaGainesvilleFL 32608USA Research Institute of Sport Science Hungarian University of Sport ScienceBudapest 1123Hungary Department of Kinesiology University of MinnesotaSt.PaulMN 55455USA Department of Musculoskeletal and Ageing Science Institute of Life Course and Medical SciencesUniversity of LiverpoolLiverpool L78TXUK

The discovery that contracting skeletal muscle generates reactive oxygen species(ROS)was first reported over 40 years *** prevailing view in the 1980s was that exercise-induced ROS production promotes oxidation of proteins and lipids resulting in muscle ***,a paradigm shift occurred in the 1990s as growing research revealed that ROS are signaling molecules,capable of activating transcriptional activators/coactivators and promoting exercise-induced muscle *** evidence supports the notion that reduction-oxidation(redox)signaling pathways play an important role in the muscle remodeling that occurs in response to endurance exercise *** review examines the specific role that redox signaling plays in this endurance exercise-induced skeletal muscle *** begin with a discussion of the primary sites of ROS production in contracting muscle fibers followed by a summary of the antioxidant enzymes involved in the regulation of ROS levels in the *** then discuss which redox-sensitive signaling pathways promote endurance exercise-induced muscle adaptation and debate the strength of the evidence supporting the notion that redox signaling plays an essential role in muscle adaptation to endurance exercise *** hopes of stimulating future research,we highlight several important unanswered questions in this field.

关键词： Antioxidants Mitochondrial biogenesis Radicals Redox signaling

A homing rescue gene drive with multiplexed gRNAs reaches high frequency in cage populations but generates functional resistance

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Journal of Genetics and Genomics 2024年第8期51卷 836-843页

作者： Shibo Hou Jingheng Chen Ruobing Feng Xuejiao Xu Nan Liang jackson Champer Center for Bioinformatics Center for Life SciencesSchool of Life SciencesPeking UniversityBeijing 100871China

CRISPR homing gene drives have considerable potential for managing populations of medically and agriculturally significant *** operate by Cas9 cleavage followed by homology-directed repair,copying the drive allele to the wild-type chromosome and thus increasing in frequency and spreading throughout a ***,resistance alleles formed by end-joining repair pose a significant *** address this,we create a homing drive targeting the essential hairy gene in Drosophila *** resistance alleles are recessive lethal,while drive carriers have a recoded“rescue”version of *** drive inheritance rate is moderate,and multigenerational cage studies show drive spread to 96%–97%of the ***,the drive does not reach 100%due to the formation of functional resistance alleles despite using four *** alleles have a large deletion but likely utilize an alternate start ***,revised designs targeting more essential regions of a gene may be necessary to avoid such functional *** of the rescue element’s native 3'UTR with a homolog from another species increases drive inheritance by 13%–24%.This was possibly because of reduced homology between the rescue element and surrounding genomic DNA,which could also be an important design consideration for rescue gene drives.

关键词： Genedrive Homing drive Rescueelement Population modification Multiplexed gRNAs Resistance alleles Cage study

Effect of coordination structure of aluminum on its activation from minerals and Oxisols during their acidification

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Pedosphere 2024年第5期34卷 916-928页

作者： Kewei LI Yangxiaoxiao SHI jackson Nkoh NKOH Jun JIANG Renkou XU State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences

The types and contents of phyllosilicate minerals in soils play an important role in soil acidification,as soil acid buffering capacity varies with the composition of the phyllosilicate *** addition to aluminum-oxygen （Al-O） octahedrons,a certain number of Al-O tetrahedrons exist in phyllosilicate minerals due to the isomorphic substitution of silicon ion (Si4+) by aluminum ion (Al3+) in Si-O tetrahedrons of ***,the effect of the two coordination structures of Al on the release of Al during mineral acidification has not yet been ***,the differences in Al activation in phyllosilicate minerals and soils with different Al coordination structures were investigated through constant-p H experiments and27Al magic-angle spinning nuclear magnetic resonance （MAS-NMR） *** results of27Al MAS-NMR spectra showed that kaolinite contained Al-O octahedrons,phlogopite and illite contained Al-O tetrahedrons,and vermiculite composite contained both octahedral and tetrahedral *** p Hvermiculite composite>phlogopite>kaolinite,which was consistent with the orders of cation exchange capacity and content of tetrahedral Al of the *** to the rate constants,the Al release rates were in the order of phlogopite>illite>vermiculite composite>kaolinite at p H *** for phlogopite,the Al release rates in these minerals increased with decreasing suspension p ***,the Al release contents and rates were greater in phlogopite,illite,and vermiculite composite containing Al-O tetrahedrons than in kaolinite containing only Al-O *** Oxisols derived from basalt with different ages were selected for similar ***27Al MAS-NMR spectra of the Oxisols showed that the 0.01-million-year （Ma） Oxisol contained both octahedral and tetrahedral Al,while the 1.33-Ma Oxisol contained only Al-O *** contents of b

关键词： Al-O octahedrons Al-O tetrahedrons aluminum release exchangeable Al phyllosilicate minerals soil acidification

Progressive meristem and single-cell transcriptomes reveal the regulatory mechanisms underlying maize inflorescence development and sex differentiation

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Molecular Plant 2024年第7期17卷 1019-1037页

作者： Yonghao Sun Liang Dong Lu Kang Wanshun Zhong David jackson Fang Yang National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070China Hubei Hongshan Laboratory Wuhan 430070China Cold Spring Harbor Laboratory Cold Spring HarborNY 11724USA School of Agriculture Sun Yat-Sen UniversityShenzhen 518107China

Maize develops separate ear and tassel inflorescences with initially similar morphology but ultimately different architecture and *** detailed regulatory mechanisms underlying these changes still remain largely *** this study,through analyzing the time-course meristem transcriptomes and floret single-cell transcriptomes of ear and tassel,we revealed the regulatory dynamics and pathways underlying inflorescence development and sex *** identified 16 diverse gene clusters with differential spatiotemporal expression patterns and revealed biased regulation of redox,programmed cell death,and hormone signals during meristem differentiation between ear and ***,based on their dynamic expression patterns,we revealed the roles of two RNA-binding proteins in regulating inflorescence meristem activity and axillary meristem ***,using the transcriptional profiles of 53910 single cells,we uncovered the cellular heterogeneity between ear and tassel *** found that multiple signals associatedwith either enhancedcell death or reduced growth are responsiblefortassel pistil suppression,while part of the gibberellic acid signal may act non-cell-autonomously to regulate ear stamen arrest during sex *** further showed that the pistil-protection gene SILKLESS 1(SK1)functions antagonistically to the known pistil-suppression genes through regulating common molecular pathways,and constructed a regulatory network for pistil-fate ***,our study provides a deep understanding of the regulatory mechanisms underlying inflorescence development and sex differentiation in maize,laying the foundation for identifying new regulators and pathways for maize hybrid breeding and improvement.

关键词： maize inflorescence floral organ sex differentiation single-cell RNA sequencing RNA-binding protein

Calcium channels caught in peripheral glia’s tug-of-war on axon regeneration in Drosophila

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Neural Regeneration Research 2025年第2期20卷 475-476页

作者： jackson Powell Tobias Steinschaden Rose Horowitz Yuanquan Song Raymond G.Perelman Center for Cellular and Molecular Therapeutics The Children’s Hospital of PhiladelphiaPhiladelphiaPAUSA The Neuroscience Graduate Group University of PennsylvaniaPhiladelphiaPAUSA Department of Pathology and Laboratory Medicine University of PennsylvaniaPhiladelphiaPAUSA Medical University of Vienna Center for Brain ResearchDepartment of NeuroimmunologyViennaAustria

Neural damage or degeneration is at the crux of many diseases,and treatment of these diseases will require the development of therapeutics to enhance and guide neural *** intrinsic and extrinsic factors dictate a neuron’s ability to regenerate,and the combination of these factors results in the great regenerative capacity of the peripheral nervous system(PNS)and the poor regenerative capacity of the central nervous system(CNS)following *** the core of a neuron’s function is its ability to relay electrochemical signals,and a neuron’s excitability is a key factor in its ability to *** works have focused on the changes in neuronal electrophysiological properties,firing patterns,and ion flux after injury,which differentially activate signaling pathways at the core of *** role of glia in neuron regeneration has long been studied.

关键词： degeneration firing system

对疼痛线索的晚期注视偏向预测慢性疼痛的维持:来自眼动的证据

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心理学报 2024年第1期56卷 44-60页

作者：杨周朱嘉雯苏琳熊明洁 Todd jackson 西南大学心理学部认知与教育部重点实验室西南大学医院重庆400715 澳门大学心理学院中国澳门999078

使用点探测视觉任务和融入真实疼痛刺激的视觉任务,以疼痛-中性、中性-中性图片为实验材料,采用眼动追踪技术,测量慢性疼痛患者对疼痛线索的动态注视偏向指标,并进一步考察这些指标对6个月后慢性疼痛强度和功能损伤变化的预测作用。研... 详细信息

使用点探测视觉任务和融入真实疼痛刺激的视觉任务,以疼痛-中性、中性-中性图片为实验材料,采用眼动追踪技术,测量慢性疼痛患者对疼痛线索的动态注视偏向指标,并进一步考察这些指标对6个月后慢性疼痛强度和功能损伤变化的预测作用。研究发现,点探测视觉任务中,慢性疼痛患者在前3个时间窗上(0~500 ms、500~1000 ms、1000~1500 ms)对疼痛线索的注视偏向显著高于对中性线索的注视偏向,但在第四个时间窗上(1500~2000ms)不存在差异;融入真实疼痛刺激的视觉任务中,慢性疼痛患者在4个时间窗上对疼痛线索的注视偏向均显著高于对中性线索的注视偏向。分层标准多元回归模型和机器学习回归模型均发现,慢性疼痛患者在两个任务中对疼痛线索的晚期注视偏向(1000~1500ms、1500~2000ms两个时间窗),均可以独立预测6个月后慢性疼痛强度和功能损伤的维持。研究结果表明,尽管慢性疼痛患者对疼痛线索从注意早期就表现出注视偏向,但是只有晚期的注视偏向能够预测慢性疼痛的维持。

关键词：慢性疼痛疼痛强度功能损伤注视偏向眼动追踪

Piling up multidecker pyrgos[n]cages as antibacterial materials

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Science China Materials 2024年

作者： Miguel A.Liuzzi-Vaamonde jackson B.Lancaster Samantha A.Mason Yuanning Feng Department of Chemistry and Biochemistry The University of Oklahoma

The development of antibiotics is regarded as one of the most significant scientific advances in modern *** the commercialization of antibiotics,infectious diseases were catastrophic throughout history[1].Penicillin was used to treat serious infections in the 1940s,but unfortunately,with the introduction of antibiotics came the emergence of antibiotic resistance[2,3].Evolved and adapted methicillin-resistant Staphylococcus aureus （MRSA） strains are presently impacting community and healthcare systems across the globe[4].

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