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Chemical Research in Chinese Universities 2012年第4期28卷 614-619页

作者： LI Jun-fenl SHI Wen-tao HAN Xiu-ying DONG Chuan CHOI martin m.f. School of Chemistry and Chemical Engineering Research Center of Environmental Science and Engineering Shanxi UniversityTaiyuan 030006P.R.China Department of Chemistry Hong Kong Baptist UniversityHong KongP.R.China

The interaction of calf thymus DNA（ctDNA） with berberine（Ber） was systematically investigated via UV-Vis,fluorescence and phosphorescence spectroscopies in aqueous solution and on solid *** very weak fluorescence intensity of Ber at 525 nm in aqueous solution can be greatly enhanced by *** UV-Vis spectrum shows that Ber could bind with DNA by *** addition,strong fluorescence of Ber alone could be observed on filter paper substrate and can be quenched by ctDNA effectively,and the increase of fluorescence polarization of Ber on the filter paper implies the intercalation *** emits phosphorescence at 619 nm in the presence of thallium（I） *** lifetime of Ber increased from 38.4 ms to 43.4 ms with the increase of *** increase of lifetime is possibly attributed to the increase of rigidity of Ber after its intercalating into the ctDNA base *** explanation is also augmented by the anionic quenching *** behaves as a typical intercalating agent into *** intrinsic binding constant between Ber and ctDNA is（1.84±0.12）×10^4 L/mol and n=0.16.

关键词： Berberine Calf thymus DNA UV-Vis spectroscopy Luminescence Interaction

Characterization of bright betatron radiation generated by direct laser acceleration of electrons in plasma of near critical density

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matter and Radiation at Extremes 2024年第2期9卷 26-35页

作者： J.Cikhardt m.Gyrdymov S.Zähter P.Tavana m.m.Günther N.Bukharskii N.Borisenko J.Jacoby X.f.Shen A.Pukhov N.E.Andreev O.N.Rosmej faculty of Electrical Engineering Czech Technical University in Prague16627 Prague 6Czech Republic Goethe University FrankfurtMax-von-Laue-Straße 160438 Frankfurt am MainGermany GSI Helmholtzzentrum.f.r Schwerionenforschung GmbH Planckstraße 164291 DarmstadtGermany focused Energy GmbH Im Tiefen See 4564293 DarmstadtGermany National Research Nuclear University mEPhI Kashirskoe shosse 31115409 MoscowRussian Federation Lebedev Physical Institute RAS Leninskiy Prospekt 53119991 MoscowRussian Federation Heinrich-Heine-University Düsseldorf Universitätsstrasse 1DüsseldorfGermany Joint Institute for High Temperatures RASIzhorskaya st.13Bldg.2125412 MoscowRussian Federation moscow Institute of Physics and Technology Institutskiy Pereulok 9141700 DolgoprudnyRussia

Directed x-rays produced in the interaction of sub-picosecond laser pulses of moderate relativistic intensity with plasma of near-critical density are investigated. Synchrotron-like (betatron) radiation occurs in the process of direct laser acceleration (DLA) of electrons in a relativisticlaser channel when the electrons undergo transverse betatron oscillations in self-generated quasi-static electric and magnetic fields. In anexperiment at the PHELIX laser system, high-current directed beams of DLA electrons with a mean energy ten times higher than the ponderomotive potential and maximum energy up to 100 meV were measured at 10^(19) W/cm^(2)laser intensity. The spectrum of directed x-raysin the range of 5–60 keV was evaluated using two sets of Ross filters placed at 0°and 10°to the laser pulse propagation axis. The differential x-ray absorption method allowed for absolute measurements of the angular-dependent photon fluence. We report 10^(13) photons/sr withenergies >5 keV measured at 0°to the laser axis and a brilliance of 10^(21) photons s^(−1) mm^(−2) mrad−2(0.1%BW)−1. The angular distributionof the emission has an fWHm of 14°–16°. Thanks to the ultra-high photon fluence, point-like radiation source, and ultra-short emissiontime, DLA-based keV backlighters are promising for various applications in high-energy-density research with kilojoule petawatt-class laserfacilities.

关键词： laser acceleration critical

Olefin Polymerization Behavior of Titanium(IV) Complexes with fluorinated and Non-fluorinated Aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer Science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim.f.magomedov Svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina Evgenii K.Golubev maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova mikhail I.Buzin Vyacheslav S.Bogdanov Boris m.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic Polymer materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(mmAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of Al/mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(m_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHmWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： fI catalysts Titanium(IV) (Co)polymerization Al/mg co-catalyst Ultra-high molecular weight polyethylene

Background removal from global auroral images:Data-driven dayglow modeling

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Earth and Planetary Physics 2024年第1期8卷 247-257页

作者： A.Ohma m.madelaire K.m.Laundal J.P.Reistad S.m.Hatch S.Gasparini S.J.Walker Birkeland Centre for Space Science Department of Physics and TechnologyUniversity of BergenBergenNorway

Global images of auroras obtained by cameras on spacecraft are a key tool for studying the near-Earth ***,the cameras are sensitive not only to auroral emissions produced by precipitating particles,but also to dayglow emissions produced by photoelectrons induced by *** emissions and scattered sunlight can contribute to the background *** fully utilize such images in space science,background contamination must be removed to isolate the auroral *** we outline a data-driven approach to modeling the background intensity in multiple images by formulating linear inverse problems based on B-splines and spherical *** approach is robust,flexible,and iteratively deselects outliers,such as auroral *** final model is smooth across the terminator and accounts for slow temporal variations and large-scale asymmetries in the *** demonstrate the model by using the three far ultraviolet cameras on the Imager for magnetopause-to-Aurora Global Exploration(ImAGE)*** method can be applied to historical missions and is relevant for upcoming missions,such as the Solar wind magnetosphere Ionosphere Link Explorer(SmILE)mission.

关键词： aurora dayglow modeling global auroral images far ultraviolet images dayglow removal

Human leukocyte antigen compatibility and incidence of donorspecific antibodies in pediatric liver transplant recipients

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World Journal of Gastroenterology 2024年第33期30卷 3837-3845页

作者： melina U melere flavia H feier Jorge Neumann Antônio N Kalil Juliana de m montagner Luiza S Nader Carolina S da Silva marco Aurélio f Junior Gabriela P Coral Guilherme P Bobsin Cristina T ferreira Department of Hepatology and Liver Transplantation Santa Casa de Porto AlegrePorto Alegre 90050170Rio Grande do SulBrazil Department of Hepato-biliary-pancreatic Surgery and Liver Transplantation Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil Postgraduation Program in medicine:Hepatology Federal University of Health Sciences of Porto AlegrePorto Alegre 90050-170Rio Grande do SulBrazil Laboratory of Transplantation Immunology Irmandade Santa Casa de Misericórdia de Porto AlegrePorto Alegre 90020-090Rio Grande do SulBrazil

BACKGROUND Antibody-mediated rejection following liver transplantation(LT)has been increasingly recognized,particularly with respect to the emergence of de novo donor-specific antibodies(DSAs)and their impact on graft *** substantial evidence for adult populations exists,research focusing on pediatric LT outcomes remains *** To investigate the prevalence of human leukocyte antigen(HLA)mismatches and DSA and evaluate their association with rejection episodes after pediatric *** A cohort of pediatric LT recipients underwent HLA testing at Santa Casa de Porto Alegre,Brazil,between December 2013 and December *** patients who survived for>30 days after LT with at least one DSA analysis were *** classes I and II and cross-matches were *** presence of de novo DSA(dnDSA)was evaluated at least 3 months after LT using the Luminex®single antigen bead method,with a positive reaction threshold set at 1000 *** episodes were confirmed by liver *** Overall,67 transplanted children were analyzed;61 received grafts from living donors,85%of whom were related to ***-transplant DSA(class I or II)was detected in 28.3%of patients,and dnDSA was detected in 48.4%.The median time to DSA detection after LT was 19.7[interquartile range(IQR):4.3-35.6]*** rejection occurred in 13 patients at follow-up,with C4d positivity observed in 5/13 Liver *** median time to rejection was 7.8(IQR:5.7-12.8)*** presence of dnDSA was significantly associated with rejection(36%vs 3%,Pfree survival rates at 12 and 24 months were 76%vs 100%and 58%vs 95%for patients with dnDSA anti-DQ vs those without,*** Our findings highlight the importance of incorporating DSA assessment into pre-and post-transplantation protocols for pediatric LT *** implications may include immunosuppression minimization strategies based on this analysis in pediatric LT recip

关键词： Human leukocyte antigens Donor-specific antibodies Liver transplantation Pediatric Rejection

Towards implementation of alloy-specific thermo-fluid modelling for laser powder-bed fusion of mg alloys

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Journal of magnesium and Alloys 2024年第6期12卷 2327-2344页

作者： mohammad Hoseini-Athar mikael Ersson Peter Hedström Department of material Science and Engineering KTH Royal Institute of TechnologyStockholmSE-10044 Sweden

multi-physics thermo-fluid modeling has been extensively used as an approach to understand melt pool dynamics and defect formation as well as optimizing the process-related parameters of laser powder-bed fusion(L-PBf).However,its capabilities for being implemented as a reliable tool for material design,where minor changes in material-related parameters must be accurately captured,is still in *** the present research,first,a thermo-fluid computational fluid dynamics(CfD)model is developed and validated against experimental *** the predicted material properties of the pure mg and commercial ZK60 and WE43 mg alloys,parametric studies are done attempting to elucidate how the difference in some of the material properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the melt pool *** is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation mass *** viscosity and wider solidification range can increase the non-uniformity of temperature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and formation of ***,the WE43 alloy showed the best behavior in terms of defect formation and evaporation mass loss,providing theoretical support to the extensive use of this alloy in *** summary,this study suggests an approach to investigate the effect of materials-related parameters on L-PBf melting and solidification,which can be extremely helpful for future design of new alloys suitable for L-PBf.

关键词： mg alloys Laser powder-bed fusion(L-PBf) melt pool dynamics Computational fluid dynamics fluid flow

促进慢性阻塞性肺疾病哮喘患者自我监控空气质量的护理干预措施: 整合性综述

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International Journal of Nursing Sciences 2024年第1期11卷 46-56页

作者： Bruna f.Sebastiao Raquel m.Hortelao Sara S.Granadas Jose m.f.ria Joana R.Pinto Helga Rafael Henriques Nursing School of Lisbon LisbonPortugal Hospital Center of Central Lisbon Portugal CUf Tejo Hospital LisbonPortugal University Hospital Center of Northern Lisbon LisbonPortugal Nursing Research Innovation and Development Centre of Lisbon(CIDNUR)LisbonPortugal

目的哮喘-慢性阻塞性肺疾病肺重叠症(Asthma-chronie obst ructive pulmonary disease overlap,A-CO)患者的生活质量较低,肺功能较差,病情经常加重。由于暴露于污染环境会加重其症状,增加发病率和病死率,环境管理对其至关重要。旨在通... 详细信息

目的哮喘-慢性阻塞性肺疾病肺重叠症(Asthma-chronie obst ructive pulmonary disease overlap,A-CO)患者的生活质量较低,肺功能较差,病情经常加重。由于暴露于污染环境会加重其症状,增加发病率和病死率,环境管理对其至关重要。旨在通过系统性综述,寻找证据,以指导制订护理干预措施,促进ACO患者对空气质量的自我管理。方法2023年3月 ,系统检索CINAHL、medline、Academie Search Complete .Scopus、WebofScience、Cochrane图书馆、乔安娜布里格斯研究所(JoannaBriggsInstitute,JBI)循证实践数据库,以及GoogleScholar。对纳人研究进行数据提取和综合,并对护理干预措施进行分类。采用JBI研究质量评估工具进行方法学质量评估。结果共纳入5篇来自不同国家的研究。促进ACO患者自我监控空气质量的干预措施包括:警觉性干预措施(医务人员定期巡诊、进行症状评估),监测干预措施(监测室内外诱发因素) ,教育干预措施(空气质量警报、避免接触过敏原),以及相关政策的影响,如无烟政策和改善空气质量的综合战略。尽管这些研究报告了不同的干预措施,方法质量也存在差异,但这些干预措施显示了预防患者病情恶化、尽量减少急诊就诊和住院治疗的潜力。这些关键点可作为护理干预措施的关键组成部分。结论有必要采取全面措施,让护士参与促进患者自我监控空气质量的多学科团队.提高认识、制订和实施护理干预,从而使ACO患者受益。同时,需要进--步开展研究,以扩大证据基础并完善这些干预措施。

关键词：空气质量哮喘哮喘-慢阻肺重叠慢性病慢性阻塞性肺疾病护理自我管理

Dynamical study of varicella-zoster virus model in sense of mittag-Leffler kernel

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International Journal of Biomathematics 2024年第3期17卷 153-183页

作者： Qura Tul Ain Aziz Khan Thabet Abdeljawad J.f.Gomez-Aguilar Saleem Riaz Department of mathematics Guizhou University GuiyangGuizhou 550025P.R.China Department of mathematics and Sciences Prince Sultan University P.O.Bor 66833 11586 RiyadhSaudi Arabia Department of medical Research China medical University Taichung 40402Taiwan CONACyT-Tecnologico Nacional de mécico/CENIDET Interior Internado Palmira S/N Col.Palmira C.P.62490CuernavacaMorelosMécico IConsejo Academico Universidad Virtual CNCIMonterreyMécico School of Automation Northwestern Polytechnical University 170072 Xian P.R.China

The primary varicella-zoster virus(VzV)infection that causes chickenpox(also known as varicella),spreads quickly among people and,in severe circumstances,can cause to fever and *** this paper,the mittag-Leffler fractional operator is used to examine the mathematical representation of the *** fractional-order differential equations are created in terms of the disease's dynamical analysis such as S:Susceptible,V:Vaccinated,E:Exposed,I:Infectious and R:*** derive the existence criterion,positive solution,Hyers-Ulam stability,and boundedness of results in order to examine the suggested fractional-order model's ***,some numerical examples for the VzV model of various fractional orders are shown with the aid of the generalized Adams-Bashforth-moulton approach to show the viability of the obtained results.

关键词： Varicella-zoster virus model Hyers-Ulam stability ABC fractional operator Schauder fix point theory numerical analysis

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang Y.Chen W.B.Yao C.Z.Xiao J.f.myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Impact of metal polluted sewage water on soil nematode assemblages in agricultural settings of Aligarh,India

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Soil Ecology Letters 2024年第1期6卷 61-75页

作者： mohammed f.S.A.Ghanem Shahid Afzal Humira Nesar Zarrin Imran Wasim Ahmad Nematode Biodiversity Research Lab Department of ZoologyAligarh Muslim UniversityAligarh 202002India

Sewage water in agriculture threatens human health and soil ecosystems through metal *** show promise as bioindicators of soil health due to their abundance and position in soil food ***-polluted water decreased abundance of certain nematode groups and Sigma maturity *** pollution positively affected nematode groups with r-selected life *** water has been inappropriately used in agriculture,posing possible threats to human health and the soil ecosystems by its constituent pollutants,especially heavy *** evaluation of its influences on soil biomes needs to consider the response of soil *** soil organisms,nematodes are seen as the best promising candidates for bioindicators of soil *** in,we collected soil samples from.f.esh water irrigated field from three sites(S1,S2 and S3)and sewage water irrigated distance gradient(5 m-40 m),to assess the influence of metal(Cu,Zn,Cd,mn,Pb)polluted water on various characteristics of nematode *** results indicated that the heavy metals decreased the abundance of C-p3 nematodes,herbivores,and predatory nematodes as well as sigma maturity index,whereas,C-p1,C-p2,bacterivore and fungivore nematodes abundance and diversity positively responded to the metal ***,nematode genera with r-selected life cycle were positively affected and those with K-selected life cycle were negatively affected by metal *** nematode community has potential to be used as indicator of pollution stress in agricultural soils to check soil health and sustainability.

关键词： heavy metals sewage irigation agriculture nematodes bioindicators