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Chinese Journal of Chemistry 1994年第1期12卷 85-94页

作者： lIU, Yu-Gang FEI, Chang-PeiInstitute of Chemistry, Chinese Academy of sciences, Beijing 100080, ChinaCHAn, Tak-Hangdepartment of Chemistry, McGill university, Montreal, PQ, canada H3A 2k6 Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China department of Chemistry McGill University Montreal PQ Canada H3A 2K6

The alkylation reaction of guanine and n-acetylguanine with model compounds such as isopropyl bromide or 4-heptyl tosylate were studied. The reaction conditions such as temperature, solvent, base, and catalyst were examined for their effects on the reaction rate, and the yield and regioselectivity of the coupling reaction. The highest yield was obtained by using DMsO as the solvent. The reaction proceeded in a homogenous manner to give higher yield of 9-n and 7-n substituted product in a mole ratio of 1:1. The ratio could be raised to 2:1 if dibenzo-18-crown-6 was used as a catalyst. Using the above procedure, three carba-DHPG analogues bearing different 1'-C alkyl side chains were synthesized.

关键词： Acyclonucleoside alkylation n-acetylguanine carba-DHPG.

Interindividual Age-Independent Differences in Human CX43 Impact Ventricular Arrhythmic Risk

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Research 2024年第3期6卷 417-432页

作者： laura García-Mendívil María Pérez-Zabalza Antoni Oliver-Gelabert JoséMaría Vallejo-Gil Javier Fañanás-Mastral Manuel Vázquez-sancho Javier AndréBellido-Morales Alexánder sebastián Vaca-núñez Carlos Ballester-Cuenca Emiliano Diez laura Ordovás Esther Pueyo Biomedical signal Interpretation and Computational simulation group(BsICos) Aragón Institute of Engineering ResearchUniversity of ZaragozaZaragoza 50018Spain BsICos Instituto de Investigación Sanitaria Aragón(IISA)Zaragoza 50018Spain Centro Universitario de la Defensa(CUD) Zaragoza 50090Spain. department of Cardiovascular surgery University Hospital Miguel ServetZaragoza 50009Spain. Institute of Experimental Medicine and Biology of Cuyo(IMBECU) CONICETMendoza 5500Argentina. Fundación Agencia Aragonesa para la Investigación y el Desarrollo(ARAID) Zaragoza 50018Spain. Biomedical Research networking Center in Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)Zaragoza 50018Spain.

Connexin 43 (CX43) is one of the major components of gap junctions, the structures responsible for the intercellular communication and transmission of the electrical impulse in the left ventricle. There is limited information on the histological changes of CX43 with age and their effect on electrophysiology, especially in humans. Here, we analyzed left ventricular biopsies from living donors starting at midlife to characterize age-related CX43 remodeling. We assessed its quantity, degree of lateralization, and spatial heterogeneity together with fibrotic deposition. We observed no significant age-related remodeling of CX43. Only spatial heterogeneity increased slightly with age, and this increase was better explained by biological age than by chronological age. Importantly, we found that CX43 features varied considerably among individuals in our population with no relevant relationship to age or fibrosis content, in contrast to animal species. We used our experimental results to feed computational models of human ventricular electrophysiology and to assess the effects of interindividual differences in specific features of CX43 and fibrosis on conduction velocity, action potential duration, and arrhythmogenicity. We found that larger amounts of fibrosis were associated with the highest arrhythmic risk, with this risk being increased when fibrosis deposition was combined with a reduction in CX43 amount and/or with an increase in CX43 spatial heterogeneity. These mechanisms underlying high arrhythmic risk in some individuals were not associated with age in our study population. In conclusion, our data rule out CX43 remodeling as an age-related arrhythmic substrate in the population beyond midlife, but highlight its potential as a proarrhythmic factor at the individual level, especially when combined with increased fibrosis.

关键词： CX43 rhythm Independent

Exploring dielectric phenomena in sulflower-like nanostructures via Monte Carlo technique

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Communications in Theoretical Physics 2024年第4期76卷 188-198页

作者： n saber Z Fadil Hussein sabbah A Mhirech B kabouchi l Bahmad Chaitany Jayprakash Raorane siva sankar sana Hassan Fouad Mohamed Hashem laboratory of Condensed Matter and Interdisciplinary sciences(laMCscI) Research Unit Labelled CNRSTURL-CNRST-17.Faculty of SciencesPO Box 1014Mohammed Ⅴ University in RabatMorocco College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait school of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea Applied Medical science department Community CollegeKing Saud UniversityPO Box 11433Riyadh Saudi Arabia department of Dental Health College of Applied Medical SciencesKing Saud UniversityPO Box 12372RiyadhSaudi Arabia

This research focuses on the electric behavior of a mixed ferrielectric sulflower-like *** structure includes a core with spin s_(i)^(Z)-1 atoms and a shell with spin σ_(j)^(Z)-5/2 *** Blume–Capel model and the Monte Carlo technique(MCt)with the Metropolis algorithm are *** are established for absolute zero,investigating stable spin configurations correlated with various physical *** MCt method explores phase transition behavior and electric hysteresis cycles under different physical parameters.

关键词： sulfower-like nanostructure dielectric characteristics Monte Carlo technique phase transition phase diagrams electric hysteresis

The neglect of nonnative orthopterans as potential invaders:A call for awareness

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Insect science 2024年第4期31卷 994-1000页

作者： Anna k.kulessa Paride Balzani Ismael soto Antonín kouba David Renault Ali serhan Tarkan Phillip J.Haubrock Ruhr university Bochum Faculty of Biology and BiotechnologyBochumGermany Faculty of Biology University of Duisburg-EssenUniversitätsstraße 5EssenGermany Faculty of Fisheries and Protection of Waters South Bohemian Research Center of Aquaculture and Biodiversity of HydrocenosesUniversity of South Bohemia in CˇeskéBudeˇjoviceVodnˇanyCzech Republic university of Rennes CNRSECOBIO(EcosystèmesBiodiversitéEvolution)UMRRennesFrance Faculty of Fisheries Department of Basic SciencesMu˘gla SıtkıKoçman UniversityMu˘glaTurkey department of life and Environmental sciences Bournemouth UniversityPooleDorsetUK Faculty of Biology and Environmental Protection Department of Ecology and Vertebrate ZoologyUniversity ofŁodzŁodzPoland department of River Ecology and Conservation Senckenberg Research Institute and Natural History Museum FrankfurtGelnhausenGermany Center for Applied Mathematics and Bioinformatics Gulf University for Science and TechnologyMubarak Al-AbdullahKuwait

Despite the potential ecological and economic impacts of invasive species,there is a dearth of data on the presence,impacts,and management implications of potentially invasive Orthoptera *** lack of research and inconsistent data,including risk screenings and impact assessments,is especially evident in ***,assessing the status,distribution,and potential threats of nonnative Orthoptera in Europe remains challenging,impeding the development of effective management *** address this gap,we call for increased efforts to collect and curate data on non-native and possibly invasive Orthoptera in *** efforts will improve our understanding of this order’s invasion dynamics,facilitate the identification of priority areas for conservation,and support the development of effective management policies and preventive measures.

关键词： costs cricket damages grasshopper impact research

Dust particle surface potential in an argonhelium plasma using the(r,q)-distribution function

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Communications in Theoretical Physics 2024年第9期76卷 141-148页

作者： Bahaaudin M Raffah A A Abid Abdullah khan Amin Esmaeili Yas Al-Hadeethi M n s Qureshi department of Physics Faculty of SciencesKing Abdulaziz UniversityJeddah 21589Saudi Arabia lithography in Devices Fabrication and Development Research Group Deanship of Scientific ResearchKing Abdulaziz UniversityJeddah 21589Saudi Arabia Joint laboratory of Plasma Application Technology Institute of Advanced TechnologyUniversity of Science and Technology of ChinaHefei230026China CAs key laboratory of Geospace Environment University of Science and Technology of ChinaHefei230026China department of Physics Zhejiang Normal UniversityJinhua321005China department of Physics Graduate School of ScienceTokyo Metropolitan UniversityMinami-Osawa 1-1Hachioji City192-0397Japan department of Physics GC UniversityLahore 54000Pakistan

In this paper,the dust particle surface potential for argon-helium plasma is evaluated analytically and numerically in the context of negatively charged dust particles by employing a power-law(r,q)-distribution *** studies have reported the argon-helium plasma and conducted a brief theoretical and experimental *** deepen our understanding further,this study aims to analyze the argon-helium plasma comprehensively using the same pattern but with the(r,q)-distribution *** this purpose,the current balance equations are derived for electron,helium and argon ions,when these charge species attain the quasineutrality *** numerically examined the currents of plasma species for a broad range of effective distribution function parameters r and *** is revealed that the surface potential of dust particles is significantly affected by the parameters r and q,helium ion-to-electron temperature ratio,argon ion-to-electron temperature ratio,and helium ion to argon ion number density *** incorporating the multi-ion(argon-helium)species,the significance of low-temperature nonMaxwellian dusty(complex)plasma is briefly examined.

关键词： dusty plasma dust charge potential plasma physics helium argon plasma r q distribution function non-Maxwellian distribution

On thermoelastic problem based on four theories with the efficiency of the magnetic field and gravity

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Journal of Ocean Engineering and science 2024年第4期9卷 338-347页

作者： A.A.kilany A.n.Abd-alla A.M.Abd-Alla s.M.Abo-Dahab department of Mathematics Faculty of ScienceSohag UniversitySohag 82524 Egypt department of Computer science Faculty of Computers and InformationLuxor UniversityEgypt department of mathematics Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The fundamental objective of this paper is to study the effectiveness of magnetic field and gravity on an isotropic homogeneous thermoelastic structure based on four theories of generalized *** another meaning,the models of coupled dynamic theory(CDT),lord-shulman(ls),Green-lindsay(Gl)as well as Green-naghdi(Gn II)will be taken in the ***,applying the harmonic method(normal mode technique),the solution of the governing equations and the expressions for the components of the displacement,temperature and(Mechanical and Maxwell’s)stresses is taken into account and calculated *** impacts of the gravity and magnetic field are illustrated graphically which are pronounced on the different physical ***,the results of some research that others have previously obtained may be found some or all of them as special cases from this study.

关键词： Generalized thermoelasticity Gravity Magnetic field Green and naghdi TheoryⅡ normal mode approach

Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： M.Grandin H.k.Connor s.Hoilijoki M.Battarbee Y.Pfau-kempf U.Ganse k.Papadakis M.Palmroth department of Physics University of HelsinkiHelsinkiFinland nAsA Goddard space Flight Center GreenbeltMD20771USA space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** solar wind Magnetosphere Ionosphere link Explorer(sMIlE)and lunar Environment heliospheric X-ray Imager(lEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their soft X-ray Imager(sXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by sMIlE sXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the sMIlE and lEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation sMIlE lEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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light(science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr s.slavich Georgy A.Ermolaev Mikhail k.Tatmyshevskiy Adilet n.Toksumakov Olga G.Matveeva Dmitriy V.Grudinin kirill V.Voronin Arslan Mazitov konstantin V.kravtsov Alexander V.syuy Dmitry M.Tsymbarenko Mikhail s.Mironov sergey M.novikov Ivan kruglov Davit A.Ghazaryan Andrey A.Vyshnevyy Aleksey V.Arsenin Valentyn s.Volkov kostya s.novoselov Moscow Center for Advanced studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. national Graphene Institute(nGI) University of ManchesterManchester M139PLUK. department of Materials science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and *** success inspired an intensive search for the highest possible anisotropic properties among vdW ***,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative ***,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical *** our approach,we found As2s3 as a highly anisotropic vdW *** demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by *** these benefits,As2s3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase ***,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

A novel diagnostic gene region for distinguishing between two pest fruit flies:Bactrocera tryoni(Froggatt)and Bactrocera neohumeralis(Hardy)(Diptera:Tephritidae)

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Insect science 2024年第4期31卷 1285-1295页

作者： Melissa l.starkie Elizabeth V.Fowler Alexander M.Piper Xiaocheng Zhu Pauline Wyatt David Gopurenko Matt n.krosch Francesca strutt karen F.Armstrong Hamish Patrick Mark k.schutze Mark J.Blacket department of Agriculture and Fisheries BiosecurityBrisbaneQueenslandAustralia Agriculture Victoria AgriBioBundooraVictoriaAustralia department of Primary Industries Wagga Wagga Agricultural InstituteWagga WaggaNew South WalesAustralia Forensic services Group Queensland Police ServiceBrisbaneQueenslandAustralia department of Pest-management and Conservation Lincoln UniversityLincolnNew Zealand Better Border Biosecurity(B3 B3nz.org.nz)LincolnNew Zealand

Bactrocera tryoni and Bactrocera neohumeralis are morphologically similar sibling pest fruit fly species that possess different biological attributes,geographic distributions,and host *** need to differentiate between the two species is critical for accurate pest status assessment,management,biosecurity,and maintenance of reference *** morphologically similar,adults may be separated based on subtle characters;however,some characters exhibit intraspecific variability,creating overlap between the two ***,there is currently no single molecular marker or rapid diagnostic assay that can reliably distinguish between *** and ***;therefore,ambiguous samples remain *** we report the first molecular marker that can consistently distinguish between *** and *** diagnostic region consists of two adjacent single nucleotide polymorphisms(snPs)within the pangolin(pan)gene *** confirmed the genotypes of each species are consistent across their distributional range,then developed a tetra-primer amplification refractory mutation system(ARMs)PCR assay for rapid diagnosis of the *** assay utilizes four primers in multiplex,with two outer universal primers,and two internal primers:one designed to target two adjacent snPs(AA)present in *** and the other targeting adjacent snPs present in ***(GG).The assay accurately discriminates between the two species,but their snP genotypes are shared with other nontarget tephritid fruit fly ***,this assay is most suited to adult diagnostics where species confirmation is necessary in determining ambiguous surveillance trap catches;maintaining pure colony lines;and in sterile Insect Technique management responses.

关键词： ARMs-PCR colony molecular diagnostics pangolin tetra-primer

A 63-Year-Old Male with D-Transposition of the Great Arteries Who Had an Early Form of the Arterial switch Operation

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Congenital Heart Disease 2024年第1期19卷 65-68页

作者： Michael A.Rebolledo Jane s.Yao Jason n.Johnson Umar s.Boston Benjamin R.Waller III Division of Pediatric Cardiology Department of PediatricsThe University of Tennessee Health Science CenterThe Heart InstituteLe Bonheur Children’s HospitalMemphisUSA College of Medicine The University of Tennessee Health ScienceMemphisUSA Division of Pediatric Cardiothoracic surgery Department of SurgeryThe University of Tennessee Health Science CenterHeart InstituteLe Bonheur Children’s HospitalMemphisUSA

We describe a 63-year-old male who appears to have undergone an early form of the arterial switch operation for D-transposition of the great arteries performed in the *** review the clinical and imaging data that support our *** had a diagnostic cardiac catheterization which demonstrated severe pulmonary hypertension responsive to epoprostenol and *** case may represent one example of the experimental surgical work done prior to *** Jatene’s description of theﬁrst successful arterial switch performed in 1975.

关键词： Adult congenital heart disease arterial switch operation great vessel anomaly imaging(all modalities)