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Peri-centrosomal localiz.tion of small interfering RNAs in C. elegans

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Science China Life Sciences 2025年

作者： Qile Jin Xuez.u Feng Minjie Hong Ke Wang Xiangyang Chen Jiewei Cheng Yan Kuang Xiaoyue si.Mingjing Xu Xinya Huang Shouhong Guang Chengming z.u Department of Obstetrics and Gynecology The First Affiliated Hospital of USTC The USTC RNA Institute Hefei National Research Center for Physical Sciences at the Microscale School of Life Sciences Division of Life Sciences and Medicine Biomedical Sciences and Health Laboratory of Anhui Province University of Science and Technology of China School of Basi. Medicine Anhui Medical University

The centrosome is the microtubule-organiz.ng center and a crucial part of cell divisi.n. Centrosomal RNAs(cnRNAs) have been reported to enable precise spatiotemporal control of gene expressi.n during cell divisi.n in many species. Whether and how cnRNAs exist in C. elegans are unclear. Here, usi.g the nuclear RNAi Argonaute protein NRDE-3 as a reporter, we observed potential peri-centrosome localiz.d small interfering(si.RNAs in C. elegans. NRDE-3 was previously shown to associate with pre-mRNAs and pre-rRNAs via a process involving the presence of complementary si.NAs. We generated a GFP-NRDE-3 knock-in transgene through CRISPR/Cas9 technology and observed that NRDE-3 formed peri-centrosomal foci neighboring the tubulin protein TBB-2, other centriole proteins and pericentriolar material(PCM)components in C. elegans embryos. The peri-centrosomal accumulation of NRDE-3 depends on RNA-dependent RNA polymerase(RdRP)-synthesi.ed 22G si.NAs and the PAz.domain of NRDE-3, which is essential for si.NA binding. Mutation of eri-1, ergo-1, or drh-3 si.nificantly increased the percentage of pericentrosome-enriched NRDE-3. At the metaphase of the cell cycle, NRDE-3 was enriched in both the peri-centrosomal region and the spindle. Moreover, the integrity of centriole proteins and pericentriolar material(PCM) components is also required for the peri-centrosomal accumulation of NRDE-3. Therefore, we concluded that si.NAs could accumulate in the pericentrosomal region in C. elegans and suggested that the peri-centrosomal region may also be a platform for RNAi-mediated gene regulation.

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Upgrading of derived pyrolysi. vapors for the production of biofuels from corncobs

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Frontiers of Chemical Science and Engineering 2018年第1期12卷 50-58页

作者： Liaoyuan Mao Yanxin Li z. Conrad z.ang State Key Laboratory of Catalysi. Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China

A bubbling fluidiz.d bed pyrolyz.r was integrated with an in-si.u honeycomb as a catalytic upgrading z.ne for the conversi.n of biomass to liquid fuels. In the upgrading z.ne, z.olite coated ceramic honeycomb （z.CH） catalysts consi.ting of z.M-5 （si. Al = 25） were stacked and N2 or recycled non-condensable gas was used as a carrier gas. Ground corncob particles were fast pyrolyz.d in the bubbling bed usi.g fine sand particles as a heat carrier and the resulting pyrolysi. vapors were passed on-line over the catalytic upgrading z.ne. The influence of carrier gas, temperature, and weight hourly space velocity （WHSV） of catalyst on the oil product properties, distribution and mass balance were studied. Usi.g z.CH effectively increased the hydrocarbon yield and the heating value of the dry oil, especially in the presence of the recycled noncondensable gas. Even a low usage of z.olite catalyst at WSHV of 180 h^-1 was effective in upgrading the pyrolysi. oil and other light olefins. The highest hydrocarbon （≥C2） and liquid aromatics yields reached to 14.23 and 4.17 wt-%, respectively. The undesi.able products including light oxygenates, furans dramatically decreased in the presence of the z.CH catalyst.

关键词： corncob monolith upgrading pyrolysi.

MODELING OF STRAIN-INDUCED PRECIPITATION KINETICS IN Nb MICROALLOYED STEELS

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Acta Metallurgica si.ica(English Letters) 2006年第5期19卷 385-390页

作者： X. G. z.ou z. Y. Liu D. Wu z. Li C.M. Li State Key Lab. of Rolling and Automation Northeastern University Shenyang 110004 China Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Engineering ＆ Research Incorporation Limited WISDRI （Wuhan Iron ＆ Steel Design and

On the basi. of the thermodynamic calculation of precipitation and consi.ering the effect of strain on the precipitation behavior and chemical composi.ion （si.and Mn）, the kinetics of precipitation from austenite has been investigated for different temperatures and strains. Nucleation theory and the solubility product of niobium, carbon, and nitrogen in austenite have been used to derive equations for the start time of precipitation as a function of temperature and composi.ion. The value of n in Avrami equation was determined usi.g the available experimental data from the published reports, which indicated that n is a constant independent of temperature and the end time of precipitation is a function of n and the start time of precipitation. The values of the start time and end time of precipitation predicted by the new model are compared with the experimental values and a good agreement was obtained between both.

关键词： strain-induced precipitation start time of precipitation end time ofprecipitation precipitation kinetics

Assessment of Metals Concentration and Ecotoxicology of the Sediment Core of Rehri Creek, Karachi Coast, Pakistan

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Acta Geologica si.ica(English Edition) 2013年第5期87卷 1434-1443页

作者： Muhammad z. CHAUDHARY Nasi. AHMAD Az.ar MASHIATULLAH Sajjad MUNIR Tariq JAVED Isotope Application Divisi.n Pakistan Institute of Nuclear Science and Technology (PINSTECH) Institute of Geology University of the Punjab Department of Earth & Environmental Sciences Bahria University Islamanad

Trace metal concentrations were investigated in a recent sediment core collected from the Rehri Creek area of the Karachi coast, si.dh - Pakistan. The core was sliced horiz.ntally at 2.5-cm intervals to determine grain si.e, sediment composi.ion, pH, organic matter, and acid-leachable trace metals： cadmium, chromium, copper, lead, and z.nc. The trace metals were analyz.d by ICP. To separate anthropogenic from geogenic input, several approaches were made, including comparison with sediment quality guidelines--ecotoxicological sense of heavy metal contamination and classi.ication by quantitative indexes. Grain-si.e analysi. and sediment composi.ion of core sample show a sandy nature with neutral pH. Elemental sequence （ES） of the trace metals is in the order of z. （19.2-109.56 ppm）〉 si.（66.46-101.71 ppm）〉 Ba （12.05-26.86 ppm）〉 As （8.18-17.36 ppm）〉 Ni （4.2- 14.69 ppm）〉 Cr （3.02-9.62 ppm）〉 Pb （2.79-6.83 ppm）〉 Cu （2.2-5.29 ppm）〉 Co （0.9-2.05 ppm）. Thus it is likely that the area may face a serious threat of metal pollution with the present deposi.ion rates unless stringent pollution control norms are adopted. The Sediment Geo-accumulation Index shows that there is no Cr, Cu, Ni, Pb, z., or Fe pollution; however, the former index and the Pollution Load Index indicate arsenic pollution in the sediments.

关键词： trace elements lake sedimentation sediment quality guidelines pollution shale values

Structure and Magnetic Properties of Boron-oxide and Boron-nitride Coated Iron Nanocapsules

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Journal of Materials Science & Technology 2010年第11期26卷 1051-1056页

作者： W.S. z.ang J.G. z.eng E. Briick P.z. si.D.Y. Geng z.D. z.ang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences China and International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110016 China College of Physi.s & Electronic Engineering Taizhou University Taizhou 317000 China Electron Probe Instrumentation Center (EPIC) Northwestern University 2225N Campus Drive 1156 MLSF Evanston IL 60208-3108 USA Van der Waals-z.eman Instituut Universiteit van Amsterdam Valckenierstraat 65 1018 XE Amsterdam The Netherlands

The boron-oxide coated iron nanocapsules have been prepared by arc-discharge in a mixture of diborane and nitrogen,and then the boron-nitride coated iron nanocapsules by a subsequent annealing under a nitrogen atmosphere at 1100 ℃.After the arc-discharge,the boron-oxide coated iron nanocapsules form,which show an amorphous surface layer of B2O3 （and/or B） and a core of γ-Fe,α-Fe,FeB *** being annealed,part of the α-Fe phase transforms to the γ-Fe phase,and the FeB phase decomposes while the BN phase *** BN shell structure formed in the BN encapsulating iron nanocapsules is *** properties of the boron-oxide coated and the boron-nitride coated iron nanocapsules were compared and discussed in terms of the particles si.es,the phase components,and the surface structures.

关键词： Arc discharge Nanocapsules Magnetic properties

Rational molecular desi.n of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution posi.ion and strength of the donors

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Science China Chemistry 2024年第5期67卷 1613-1623页

作者： Changfeng si.Dianming Sun Tomas Matulaitis David B.Cordes Alexandra M.z.Slawin Eli z.sman-Colman Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we desi.ned and synthesi.ed four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2GCz.BP, 2DPACz.BP, 2FBP2GCz.and 2FBP2DPACz. We systematically investigated the effect of substitution posi.ion and strength of donors on the optoelectronic properties. The reverse intersystem crossi.g rate constant(kRISC) of the emitters having donors substituted at posi.ions 11and 12 of the dibenz.[a,c]phenaz.ne(BP) is more than 10-times faster than that of compounds substituted having donors substituted at posi.ions 3 and 6. Compound 2DPACz.BP, containing stronger donors than 2GCz.BP, exhibits a red-shifted emissi.n and smaller si.glet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DPACz.BP doped in m CP emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved si.nificantly by usi.g 4Cz.IPN as an assi.tant dopant in a hyperfluorescence(HF) configuration, where the 2DPACz.BP HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF SP-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processi.g red OLEDs dibenz.[a,c]phenaz.ne dendrimers

Synthesi. of TiN/a-si.3N_4 thin film by usi.g a Mather type dense plasma focus system

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Chinese Physi.s B 2013年第5期22卷 381-385页

作者： T. Hussain R. Ahmad N. Khalid z. A. Umar A. Hussnain Center For Advanced Studies in Physi.s (CASP) 1-Church RoadGC University Department of Physi.s Government College University

A 2.3 kJ Mather type pulsed plasma focus device was used for the synthesi. of a TiN/a-si.N4 thin film at room temperature. The film was characteriz.d usi.g X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, scanning electron microscopy （SEM）, and atomic force microscopy （AFM）. The XRD pattern confirms the growth of polycrystalline TiN thin film. The XPS results indicate that the synthesi.ed film is non-stoichiometric and contains titanium nitride, si.icon nitride, and a phase of si.icon oxy-nitride. The SEM and AFM results reveal that the surface of the synthesi.ed film is quite smooth with 0.59 nm roughness （root-mean-square）.

关键词： plasma focus TiN/a-si.N4 films X-ray diffraction

High Temperature Oxidation and Wear Resi.tance of Y-modified Hot Dipping Aluminiz.d Coating on SCH12 Steel

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稀有金属材料与工程 2012年第S1期41卷 231-235页

作者： Fan, X. S. Yang, z. G. z.ang, C. Tsi.ghua Univ Dept Mat Sci & Engn State Key Lab New Ceram & Fine Proc Beijing 100084 Peoples R China

Microstructures,high-temperature oxidation and wear resi.tance of hot dipping Al-si.Y coating on SCH12 heat resi.tant cast steel were investigated in this *** aluminiz.d coating was characteriz.d by scanning electron microscopy(SEM),energy dispersi.e X-ray spectrometry(EDX)and X-ray diffraction(XRD).The results showed that the coating was composed of the Al-rich outer layer and the intermetallics inner *** the Al-rich layer,some Y-rich precipitates and Fe-Al-si.Cr precipitates could be *** intermetallics layer presented three layers induced by the increase of Fe,Cr,Ni content and the corresponding decrease of Al,si.*** oxidation tests were conducted in still air at 850℃for up to 100 *** oxidation,a top oxide scale composed of mainlyα-Al2O3,Al5Y3O12 was formed on the steel *** intermetallics beneath the oxide scale consi.ted of mainly FeAl and small amount of Fe2Al5 and Cr3si.*** mass gain of the coated and uncoated SCH1steel is 0.45 mg/cm 2 and 0.57 mg/cm 2,*** wear resi.tance was investigated usi.g a high-temperature pin-on-disc tribometer at 650℃.The wear rate for the coated and uncoated steel is 0.45μm 3 /μm.N and 3.01μm 3 /μm.N,*** high temperature wear tests and oxidation tests results demonstrated that the yttrium-modified aluminiz.d specimen had si.nificantly improved high-temperature wear resi.tance and equivalent oxidation resi.tance compared with the original SCH12 specimen.

关键词： hot dipping aluminiz.ng oxidation resi.tance high-temperature wear resi.tance

Epigenetic regulation of plant immunity:from chromatin codes to plant disease resi.tance

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aBIOTECH 2023年第2期4卷 124-139页

作者： si.si.Xie Cheng-Guo Duan Shanghai Center for Plant Stress Biology and CAS Center for Excellence in Molecular Plant Sciences Chinese Academy of SciencesShanghai 200032China Universi.y of the Chinese Academy of Sciences Beijing 100049China

Facing a deteriorating natural environment and an increasi.g serious food crisi.,bioengineering-based breeding is increasi.g in *** defend against pathogen infection,plants have evolved multiple defense mechanisms,including pathogen-associated molecular pattern(PAMP)-triggered immunity(PTI)and effector-triggered immunity(ETI).A complex regulatory network acts downstream of these PTI and ETI pathways,including hormone si.nal transduction and transcriptional *** recent years,increasi.g lines of evidence show that epigenetic factors act,as key regulators involved in the transcriptional reprogramming,to modulate plant immune ***,we summariz. current progress on the regulatory mechanism of DNA methylation and histone modifications in plant defense *** addition,we also discuss the application of epigenetic mechanism-based resi.tance strategies in plant disease breeding.

关键词： Histone modification DNA methylation Transcriptional reprogramming Plant immunity Disease resi.tance