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traveling wave solutions of the nonlinear Gilson-Pickering equation in crystal lattice theory

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Journal of ocean Engineering and Science 2024年第1期9卷 40-49页

作者： A.t.Nguyen o.Nikan Z.Avazzadeh Division of Applied Mathematics Science and Technology Advanced InstituteVan Lang UniversityHo Chi Minh CityVietnam Faculty of technology Van Lang UniversityHo Chi Minh CityVietnam School of Mathematics Iran University of Science and TechnologyNarmakTehranIran Department of Applied Mathematics Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China

this paper focuses on obtaining the traveling wave solutions of the nonlinear Gilson-Pickering equa-tion(GPE),which describes the prorogation of waves in crystal lattice theory and plasma physics.the solution of the GPE is approximated via the finite difference technique and the localized meshless radial basis function generated finite difference.the association of the technique results in a meshless approach that does not require linearizing the nonlinear terms.At the first step,the PDE is converted to a system of nonlinear oDEs with the help of the radial kernels.In the second step,a high-order oDE solver is adopted to discretize the nonlinear oDE system.the global collocation techniques pose a considerable computationl burden due to the calculation of the dense algebraic system.the proposed method approx-imates differential operators over the local support domain,leading to sparse differentiation matrices and decreasing the computational burden.Numerical results and comparisons are provided to confirm the efficiency and accuracy of the method.

关键词： Nonlinear Gilson–Pickering equation Soliton wave solutions Meshless technique RBF LRBF-FD optimal shape parameter

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall o.Hetherington t.W.Buggey t.Arnold M.W.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their performance.In order to understand the changes of the CCD370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance level.three CCDs have been characterised,the two flight devices and the flight spa re.this has been carried out at the open University in a bespo ke cleanroom measure ment facility.the results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe rature.However at the nominal ope rating tempe rature(-120℃) it is within the procure ment specifications.overall,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science mode.the se rial charge transfer inefficiency degrades with temperature in full frame mode.However any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

Detailed seismic zoning of the East Kazakhstan region in the Republic of Kazakhstan

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Geodesy and Geodynamics 2024年第2期15卷 156-165页

作者： Natalya V.Silacheva N.P.Stepanenko o.K.Kurilova A.D.Kudabayeva A.t.Danabayeva Institute of Seismology Ministry of Emergency SituationsAlmaty 050060Kazakhstan

Kazakhstan is currently drafting new construction regulations that comply with the major provisions of the Eurocodes.Such regulations are created on the basis of seismic zoning maps of various degrees of detail,developed by our Institute of Seismology using a new methodological approach for Kazakhstan.the article is about creating the first normative map of the Detailed Seismic Zoning on a probabilistic foundation for the Republic of Kazakhstan’s East Kazakhstan region.We carried out the probabilistic assessment of seismic hazard using a methodology consistent with the main provisions of Eurocode 8and updated compared with that used in developing maps of Kazakhstan’s General Seismic Zoning and seismic microzoning of Almaty.the most thorough and current data accessible for the area under consideration were combined with contemporary analytical techniques.Updates have been done to not only the databases being used but also the way seismic sources were shown,including active faults now.on a scale of 1:1000000,precise seismic zoning maps of the East Kazakhstan region were created for two probabilities of exceedance:10%and 2%in 50 years in terms of peak ground accelerations and macroseismic intensities.the obtained seismic hazard distribution is generally consistent with the General Seismic Zoning of Kazakhstan’s previous findings.However,because active faults were included and a thoroughly revised catalog was used,there are more pronounced zones of increased danger along the fault in the western part of the region.In the west of the territory,acceleration values also increased due to a more accurate consideration of seismotectonic conditions.Zoning maps are the basis for developing new state building regulations of the Republic of Kazakhstan.

关键词： Probabilistic seismic hazard assessment Detailed seismic zoning Peak ground acceleration Microseismical intensity

Highly Defective Dark tio_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties

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transactions of tianjin University 2024年第2期30卷 198-209页

作者： E.D.Fakhrutdinova o.A.Reutova t.A.Bugrova I.Yu.ovsyuk L.S.Kibis o.A.Stonkus D.B.Vasilchenko o.V.Vodyankina V.A.Svetlychnyi National Research tomsk State University TomskRussia 634050 Novosibirsk State University NovosibirskRussia 630090 Boreskov Institute of Catalysis NovosibirskRussia 630090 Nikolaev Institute of Inorganic Chemistry NovosibirskRussia 630090

the study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed Co adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (oH) _(2) (No _(3) ) _(8) ] were used. the sample featured a high content of single-atom species and subnano-sized Pt clusters. the X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the tio _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. the 0.5Pt(C)/tio_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation.

关键词： Dark(black)tio_(2) Pulsed laser ablation Platinum reduction method Precursor type Photocatalysis Hydrogen evolution reaction

the CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.W.J.Hubbard o.Hetherington D.J.Hall t.W.Buggey S.Parsons t.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

the ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.the Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.the shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.therefore,two radiation environments can be approximated based on the shutter door position:open and closed.the instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.the results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.this is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Liver surface depressions in the presence of diaphragmatic muscular bands on trans-illumination

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World Journal of Experimental Medicine 2024年第2期14卷 5-10页

作者： Shamir o Cawich Michael t Gardner Ramanand Shetty Jean Pierre Louboutin Zenica Dabichan Shaneeta Johnson Department of Surgery University of the West IndiesSt AugustineTrinidad and Tobago Section of Anatomy Department of Basic Medical SciencesUniversity of the West IndiesKingston KIN7Jamaica Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States

traditional descriptions of liver anatomy refer to a smooth,convex surface contacting the diaphragm.Surface depressions are recognized anatomic variants.there are many theories to explain the cause of the depressions.... 详细信息

关键词： Liver Anatomy Depressions Fissure Groove Sulcus Variant

Hepatic grooves:An observational study at laparoscopic surgery

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World Journal of Experimental Medicine 2024年第2期14卷 97-102页

作者： Shamir o Cawich Dexter A thomas Fawwaz Mohammed Michael t Gardner Marlene Craigie Shaneeta Johnson Ramnanand S Kedambady Department of Surgery University of the West IndiesSt Augustine 000000Trinidad and Tobago Department of Surgery Port of Spain General HospitalPort of Spain 000000Trinidad and Tobago Section of Anatomy Basic Medical SciencesUniversity of the West IndiesKingston 000000Jamaica Department of Radiology University of the West IndiesKingston 000000Jamaica Department of Surgery Morehouse School of MedicineAtlantaGA 30310United States Section of Anatomy Department of Basic Medical SciencesUniversity of the West IndiesKingston KIN7Jamaica

BACKGRoUND In traditional descriptions,the upper surface of the liver is smooth and convex,but deep depressions are variants that are present in 5%-40%of patients.We sought to determine the relationship between surface depressions and the diaphragm.AIM to use exploratory laparoscopy to determine the relationship between surface depressions and the diaphragm.MEtHoDS An observational study was performed in all patients undergoing laparoscopic upper gastro-intestinal operations between January 1,2023 and January 20,2024.A thirty-degree laparoscope was used to inspect the liver and diaphragm.When surface depressions were present,we recorded patient demographics,presence of diaphragmatic bands,rib protrusions and/or any other source of compression during inspection.RESULtS of 394 patients,343 had normal surface anatomy,and 51(12.9%)had prominent surface depressions on the liver.there was no significant relationship between the presence of surface depressions and gender nor the presence of rib projections.However,there was significant association between the presence of surface depressions and diaphragmatic muscular bands(PoNCLUSIoN With these data,the diaphragmatic-band theory has gained increased importance over other theories for surface depressions.Further studies are warranted using cross sectional imaging to confirm relationships with intersectional planes as well as beta-catenin assays in the affected liver parenchyma.

关键词： Liver Variant Vein Hepatic Surgery

Academic productivity correlates with industry earnings in foot and ankle fellowship programs in the United States:A retrospective analysis

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World Journal of orthopedics 2024年第2期15卷 129-138页

作者： Albert t Anastasio Anthony N Baumann Kempland C Walley Kyle J Hitchman Conor o’Neill Jonathan Kaplan Samuel B Adams Department of orthopedic Surgery Duke University HospitalDurhamNC 27710United States College of Medicine Northeast Ohio Medical UniversityRootstownOH 44272United States Department of orthopedic Surgery University of MichiganAnn ArborMI 48109United States School of osteopathic Medicine Campbell UniversityLillingtonNC 27546United States

BACKGRoUND the study investigates the connection between academic productivity and industry earnings in foot and ankle orthopedic surgery fellowships.Utilizing metrics like the H-index and open Payments Database(oPD)data,it addresses a gap in understanding the relationship between scholarly achievements and financial outcomes,providing a basis for further exploration in this specialized medical field.AIM to elucidate the trends between academic productivity and industry earnings across foot and ankle orthopedic surgery fellowship programs in the United States.MEtHoDS this study is a retrospective analysis of the relationship between academic productivity and industry earnings of foot and ankle orthopedic surgery fellowships at an individual faculty and fellowship level.Academic productivity was defined via H-index and recorded from the Scopus website.Industry earnings were recorded from the oPD.RESULtS Forty-eight foot and ankle orthopedic surgery fellowships(100%of fellowships)in the United States with a combined total of 165 physicians(95.9%of physicians)were included.Mean individual physician(n=165)total life-time earnings reported on the oPD website was United States Dollar(USD)451430.30±1851084.89(range:USD 25.16-21269249.85;median:USD 27839.80).Mean physician(n=165)H-index as reported on Scopus is 14.24±12.39(range:0-63;median:11).there was a significant but weak correlation between individual physician H-index and individual physician total life-time earnings(Po=0.334)and a significant and moderate positive correlation between combined fellowship H-index and total life-time earnings per fellowship(P=0.004,Spearman’s rho=0.409).CoNCLUSIoN there is a significant and positive correlation between academic productivity and industry earnings at foot and ankle orthopedic surgery fellowships in the United States.this observation is true on an individual physician level as well as on a fellowship level.

关键词： Sunshine act Foot and ankle orthopedic surgery orthopedic fellowship Industry earnings

Late ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： David A.t.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： ordovician LoME paleoecology palaeobiogeography biotas