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Exploring the characteristics of the flare from PMN J0218–2307 by Fermi-LAT

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Research in Astronomy and Astrophysics 2021年第7期21卷 17-22页

作者： yun-chuan xiang Yu-Liang Xin Min Yuan Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming650091China School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China

PMN J0218-2307(4 FGL J0218.9-2305) is classified as a blazar candidate with unknown type(BCU) in the fourth source catalog from the Fermi Large Area Telescope(Fermi-LAT).With the updated Fermi-LAT Pass 8 data,the γ-ray flaring activity toward PMN J0218-2307 is *** test statistic(TS) value of PMN J0218-2307 in energy band of 100 MeV-500 GeV is 133.893 with a significance level of 10.96σ.The maximum-likelihood photon flux is(8.131 ± 1.359) × 10^(-9) ph cm^(-2) s^(-1).A significantγ-ray flare in the period from 2008 August 4 to 2019 August 25 is found from the *** spectral characteristics of GeV energy band of PMN J0218-2307 is similar to that of flat-spectrum radio quasars(FSRQs) in the local Universe.

关键词： radiation mechanisms:non-thermal gamma rays:galaxies galaxies:active galaxies:individual(PMN J0218–2307)

The likely counterpart to γ-ray excess from the northwest region of Arp 220

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Research in Astronomy and Astrophysics 2021年第7期21卷 171-176页

作者： yun-chuan xiang Jun-Hao Deng Ze-Jun Jiang Department of Astronomy Yunnan Universityand Key Laboratory of Astroparticle Physics of Yunnan ProvinceKunming 650091China

The unknown γ-ray excess in the northwest region of Arp 220 was revisited by analyzing~11.8 years of the Fermi Large Area Telescope(Fermi-LAT) data in this *** found that its photon flux was approximately three times higher than that of the previous study in the 0.2-100 GeV band,and the corresponding significance level ~8.15σ was approximately four times higher than *** light curves of 15 and 45 time bins from the whole time all showed two active periods,and the variability of the second period was more significant than that of the first *** spectral indices from the two active periods were not statistically different and were close to the range of γ-ray flat-spectrum radio quasars observed by *** the position of CRATES J153246+234400 was consistent with the best-fit position of our analysis,we suggest that CRATES J153246+234400 is more likely a γ-ray counterpart for the variational *** Arp 220,there was no significant variability in the γ-ray emission.

关键词： flat spectrum radio quasar:individual(CRATES J153246+234400) quasars γ-ray emission

Intelligent responsive self-assembled micro-nanocapsules: Used to delay gel gelation time

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Petroleum Science 2024年第4期21卷 2433-2443页

作者： chuan-Hong Kang Ji-xiang Guo Dong-Tao Fei Wyclif Kiyingi Unconventional Petroleum Research Institute China University of Petroleum

In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can "go further" in the formation,but the most of the methods for delaying gel gelation time are complicated or have low *** is an urgent need for an effective method for delaying gel gelation time with intelligent *** by the slow-release effect of drug capsules,this paper uses the self-assembly effect of gas-phase hydrophobic SiO2in aqueous solution as a capsule to prepare an intelligent responsive self-assembled *** capsule slowly releases the cross-linking agent under the stimulation of external conditions such as temperature and pH value,thus delaying gel gelation *** the pH value is 2 and the concentration of gas-phase hydrophobic SiO2particles is 10%,the gelation time of the capsule gel system at 30,60,90,and 120℃ is12.5,13.2,15.2,and 21.1 times longer than that of the gel system without containing capsule,*** with other methods,the yield stress of the gel without containing capsules was 78 Pa,and the yield stress after the addition of capsules was 322 *** intelligent responsive self-assembled micronanocapsules prepared by gas-phase hydrophobic silica nanoparticles can not only delay the gel gelation time,but also increase the gel *** slow release of cross-linking agent from capsule provides an effective method for prolongating the gelation time of polymer gels.

关键词： Profile control and water shutoff Polymer gel Delayed gelation time Intelligent response Self-assembled Micro-nanocapsules

Glaucoma drainage device implantation and cyclophotocoagulation in the management of refractory glaucoma after Descemet-stripping automated endothelial keratoplasty

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 257-264页

作者： Min-Shu Wang Xue-chuan Dong Mi-yun Zheng xiang Fan Ge-Ge Xiao Jing Hong Ling-Ling Wu Department of Ophthalmology Peking University Third HospitalBeijing 100191China Key Laboratory of Restoration of Damaged Ocular Nerve Beijing 100191China NIMO Ophthalmology Research Institute Beijing 100176China Department of Ophthalmology the First Hospital of PutianTeaching HospitalFujian Medical UniversityPutian 351100Fujian ProvinceChina

AIM:To compare the surgical outcomes of glaucoma drainage device implantation(GDI)and trans-scleral neodymium:YAG cyclophotocoagulation(CPC)in the management of refractory glaucoma after Descemetstripping automated endothelial keratoplasty(DSAEK).METHODS:This retrospective study on observational case series enrolled 29 patients who underwent DSAEK and posterior anti-glaucoma surgery(15 with GDI and 14 with CPC).The main outcome measures were intraocular pressure(IOP),glaucoma surgery success rate(defined as IOP of 6–21 mm Hg without additional anti-glaucoma operation),number of glaucoma medications,endothelial graft status,and best-corrected visual acuity(BCVA).RESULTS:The mean follow-up time was 34.1 and 21.0mo for DSAEK or glaucoma surgeries,both for the GDI and CPC *** groups showed significant IOP reduction after glaucoma *** GDI group presented a significantly higher success rate in IOP control than the CPC group(60%vs 21.4%,P=0.03).Both procedures significantly decreased the number of glaucoma medications(P=0.03).Forty percent and 57%of cases in the GDI and the CPC group,respectively,experienced endothelial graft failure during follow-up(P=0.36).Significantly worse BCVA after surgery was observed in the CPC group but not in the GDI ***:Both GDI and CPC significantly decrease IOP in eyes with glaucoma after *** is preferable to CPC in refractory glaucoma cases after DSAEK,as it manifests a significantly higher success rate for IOP control,similar endothelial graft failure rate,and relatively preserves BCVA than CPC.

关键词： glaucoma drainage device implantation cyclophotocoagulation refractory glaucoma Descemetstripping automated endothelial keratoplasty

Electronic structural engineering of bimetallic Bi-Cu alloying nanosheet for highly-efficient CO_(2) electroreduction and Zn-CO_(2) batteries

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Nano Research 2024年第5期17卷 3684-3692页

作者： Wenbo Wu Jiaye Zhu yun Tong Shuangfei xiang Pengzuo Chen School of Chemistry and Chemical Engineering Key Laboratory of Surface and Interface Science of Polymer Materials of Zhejiang ProvinceZhejiang Sci-Tech UniversityHangzhou 310018China

Regulating the electronic structure of Bi-based materials by alloying engineering is promising to promote the electrocatalytic activity,but it remains some challenges to be *** this study,a facile electrochemical co-deposition strategy is developed to synthesize the bimetallic Bi_(9)Cu_(1) alloy nanosheet on carbon cloth(Bi_(9)Cu_(1)/CC),which represents a novel self-supporting electrode for the electrocatalytic carbon dioxide(CO_(2))reduction reaction(CO_(2)RR).The Bi_(9)Cu_(1)/CC catalyst has achieved a remarkable catalytic performance with high Faradaic efficiencies(FE)of over 90%for formate at wide potentials from-0.7 to-1.2 V *** hydrogen electrode(RHE).Moreover,the reversible Zn-CO_(2) battery can be driven by Bi_(9)Cu_(1)/CC cathode with a largest power density of 1.4 mW·cm^(-2),and superior operating *** systematic characterizations and electrochemical results confirm that the improved catalytic active sites,the enhanced mass/charge transport and the optimal reaction kinetics of Bi nanosheet are realized for CO_(2)RR by Cu *** situ attenuated total reflection infrared(ATR-IR)result confirms the bimetallic Bi-Cu active sites prefer to follow the^(*)OCHO conversion *** density functional theory(DFT)calculations suggest that the Cu alloying contributes to the increased density of states near the Fermi surface of Bi and the optimized adsorption of^(*)OCHO intermediates on the Bi sites,resulting in the excellent catalytic performance.

关键词： electronic regulation bismuth nanosheet copper alloying CO_(2)electroreduction Zn-CO_(2)batteries

NFXL1 functions as a transcriptional activator required for thermotolerance at reproductive stage in Arabidopsis

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Journal of Integrative Plant Biology 2024年第1期66卷 54-65页

作者： Qiao‐yun Zhu Lin‐Lin Zhang Jian‐xiang Liu State Key Laboratory of Plant Environmental Resilience College of Life SciencesZhejiang UniversityHangzhou 310027China

Plants are highly susceptible to abiotic stresses,particularly heat stress during the reproductive ***,the specific molecular mechanisms underlying this sensitivity remain largely *** the current study,we demonstrate that the Nuclear Transcription Factor,X-box Binding Protein 1-Like 1(NFXL1),directly regulates the expression of DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 2A(DREB2A),which is crucial for reproductive thermotolerance in ***1 is upregulated by heat stress,and its mutation leads to a reduction in silique length(seed number)under heat stress ***-Seq analysis reveals that NFXL1 has a global impact on the expression of heat stress responsive genes,including DREB2A,Heat Shock Factor A3(HSFA3)and Heat Shock Protein 17.6(HSP17.6)in flower ***,NFXL1 is enriched in the promoter region of DREB2A,but not of either HSFA3 or *** experiments using electrophoretic mobility shift assay have confirmed that NFXL1 directly binds to the DNA fragment derived from the DREB2A ***,effector-reporter assays have shown that NFXL1 activates the DREB2A *** DREB2A mutants are also heat stress sensitive at the reproductive stage,and DEREB2A is epistatic to NFXL1 in regulating thermotolerance in flower *** is known that HSFA3,a direct target of DREB2A,regulates the expression of heat shock proteins genes under heat stress ***,our findings establish NFXL1 as a critical upstream regulator of DREB2A in the transcriptional cassette responsible for heat stress responses required for reproductive thermotolerance in Arabidopsis.

关键词： Arabidopsis DREB2A heat stress NFXL1 reproductive thermotolerance

Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： Peng SI Qing-xiang LI Xiao-Yang CHEN Min WANG chuan-Jun LUO Tianjin Meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China Shaoguan Meteorological Service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin Meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period

Comment on“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 109-110页

作者： xiang-Yan Liu yun-Yang Xu Ze xiang Shu-Sen Zheng Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical College Hangzhou 310015China Zhejiang University School of Medicine Hangzhou 310009China

To the Editor:We read with great interest the article by Schulze et ***“Robotic surgery and liver transplantation:A single-center experience of 501 robotic donor hepatectomies”[1].It is the first single-center report including over 500 fully robotic donor *** the donors,the overall complication rate was 6.4%(n=32).Postoperative self-limiting bleeding(0.4%)and bile leakage from the resection plane(1.8%)were rare.

关键词： robotic Robotic center

Geochemical fractionation and potential release behaviour of heavy metals in lead–zinc smelting soils

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Journal of Environmental Sciences 2024年第5期139卷 1-11页

作者： Xinghua Luo Chao xiang chuan Wu Wenyan Gao Wenshun Ke Jiaqing Zeng Waichin Li Shengguo Xue School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution Central South UniversityChangsha 410083China Department of Science and Environmental Studies The Education University of Hong KongHong Kong 999077China

The lack of understanding of heavy metal speciation and solubility control mechanisms in smelting soils limits the effective pollution *** this study smelting soils were investigated by an advanced mineralogical analysis(AMICS),leaching tests and thermodynamic *** aims were to identify the partitioning and release behaviour of Pb,Zn,Cd and *** integration of multiple techniques was necessary and displayed coherent *** addition to the residual fraction,Pb and Zn were predominantly associated with reducible fractions,and As primarily existed as the crystalline iron oxide-bound *** quantitative analysis further confirmed that Fe oxyhydroxides were the common dominant phase for As,Cd,Pb and *** addition,a metal arsenate(paulmooreite)was an important mineral host for Pb and *** pH-stat leaching indicted that the release of Pb,Zn and Cd increased towards low pH values while release of As increased towards high p H *** separate leaching schemes were associated with the geochemical behaviour under the control of minerals and were confirmed by thermodynamic *** calculations suggested that the formation of arsenate minerals(schultenite,mimetite and koritnigite)and the binding to Fe oxyhydroxides synchronously controlled the release of Pb,Zn,Cd and *** results emphasized the governing role of Fe oxyhydroxides and secondary insoluble minerals in natural attenuation of heavy metals,which provides a novelty strategy for the stabilization of multi-metals in smelting sites.

关键词： Smelting soils Heavy metal Fractionation AMICS Geochemical modelling