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Cross-method Analysis of Corotation Radii Data set for spiral Galaxies

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Research in Astronomy and Astrophysics 2024年第7期24卷 95-110页

作者： V.s.Kostiuk A.A.Marchuk A.s.Gusev sternberg Astronomical Institute Lomonosov Moscow State UniversityUniversitetsky pr.13119234 MoscowRussia Central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1196140 St.PetersburgRussia saint Petersburg state University Universitetsky pr.28198504 St.PetersburgRussia

A corotation radius is a key characteristic of disk galaxies that is essential to determine the angular speed of the spiral structureΩ_p,and therefore understand its *** the literature,there are plenty of methods to estimate this value,but do these measurements have any consistency?In this work,we collected a data set of corotation radius measurements for 547 galaxies,300 of which had at least two *** initial analysis reveals that most objects have rather inconsistent corotation radius ***,a significant fraction of galactic disks is distinguished by a large error coverage and almost uniform distribution of *** findings do not have any relation to spiral type,Hubble classification,or presence of a *** other reasons,obtained results could be explained by the transient nature of.s.irals in a considerable part of *** have made our collected data sample publicly available,and have demonstrated on one example how it could be useful for future research by investigating a winding time value for a sample of galaxies with possible multiple spiral arm patterns.

关键词： galaxies fundamental parameters-galaxies kinematics and dynamics-galaxies structure

Endoscopic treatment of biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants: Lessons learned from single-balloon enteroscopy-assisted ERCP

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 509-514页

作者： Rodrigo Garcés-Durán Laurent Monino Pierre H Deprez Hubert Piessevaux Tom G Moreels Department of Gastroenterology and Hepatology Universitécatholique de LouvainCliniques Universitaires Saint-LucAvenue Hippocrates 101200 BrusselsBelgium

Background: Endoscopic treatment of biliopancreatic pathology is challenging due to surgically altered anatomy after Whipple's pancreaticoduodenectomy. This study aimed to evaluate the feasibility and safety of.s.ngle-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography(sBE-ERCP) to treat biliopancreatic pathology in patients with Whipple's pancreaticoduodenectomy surgical variants. Methods: We retrospectively analyzed 106 sBE-ERCP procedures in 46 patients with Whipple's variants. Technical and clinical success rates and adverse events were evaluated. Results: Biliary sBE-ERCP was performed in 34 patients and pancreatic sBE-ERCP in 17, including 5 with both indications. from a total of 106 sBE-ERCP procedures, 76 were biliary indication with technical success rate of 68/76(90%) procedures and clinical success rate of 30/34(88%) patients. Mild adverse event rate was 8/76(11%), without serious adverse events. from a total of 106 sBE-ERCP procedures, 30 were pancreatic indication with technical success rate of 24/30(80%) procedures( P = 0.194 vs. biliary sBEERCP) and clinical success rate of 11/17(65%) patients( P = 0.016 vs. biliary sBE-ERCP). Mild adverse event rate was 6/30(20%)( P = 0.194 vs. biliary sBE-ERCP), without serious adverse events. After sBE-ERCP failure, endoscopic ultrasound-guided drainage, percutaneous drainage and redo surgery were alternative therapeutic options. Conclusions: Biliopancreatic pathology after Whipple's pancreaticoduodenectomy variants can be treated using sBE-ERCP without serious adverse events. Technical and clinical success rates are high for biliary indications, whereas clinical success rate of pancreatic indications is significantly lower. sBE-ERCP can be considered as first-line treatment option in this patient group with surgically altered anatomy.

关键词： Enteroscopy Endoscopic retrograde cholangiopancreatography Pancreaticoduodenectomy surgically altered anatomy Whipple’s procedure

Two-stream Approximation to the Radiative Transfer Equation:A New Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA L.Akana NGUIMDO DNJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed New Method using the fundamental definition of two-stream approximation(f-TsA) developed in a previous work. Notably,New Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, New Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method Legendre polynomial optical thickness moments of.s.ecific intensity conversion function transmittance reflectance

Photometric and spectroscopic study of Ten Low Mass Ratio Contact Binary systems:Orbital stability,O'Connell Effect and Infrared Calcium Line filling

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Research in Astronomy and Astrophysics 2024年第8期24卷 212-222页

作者： surjit s.Wadhwa Adam Popowicz Raúl Michel Petar Kostić Oliver Vince Nick f.H.Tothill Ain Y.De Horta Miroslav D.filipović school of.s.ience Western Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia Department of Electronics Electrical Engineering and MicroelectronicsSilesian University of TechnologyAkademicka 1644120 GliwicePoland Instituto de Astronomía UNAM.A.P.87722800 EnsenadaBCMéxico Astronomical Observatory Volgina 711060 BelgradeSerbia

Low mass ratio contact binary systems are more likely to have unstable orbits and potentially *** addition,such systems exhibit characteristics such as starspots and high energy emissions(UV)suggestive of chromospheric and magnetic *** curve modeling of ten contact binary systems is *** were found to be of extreme low mass ratio ranging from 0.122 to 0.24 and three were found to be potentially unstable and possible merger *** of the infrared calcium absorption lines is a marker of increased chromospheric *** use the available Large sky Area Multi-Object fiber spectroscopic Telescope spectra along with matched standard spectra(broadened for rotation)to measure the excess filling of the central core depression flux of the two main infrared calcium absorption linesλ8542 andλ*** find that all reported contact binaries have excess filling of the core flux in the infrared calcium *** of the systems reported were also observed by the Galaxy Evolution Explorer mission and we find that all three have features of excess ultraviolet emissions further adding evidence for increased chromospheric activity in low mass ratio contact *** of both orbital stability and absorption line filling is dependent on the determination of geometric and absolute parameters from light curve *** an insignificant number of contact binary light curves exhibit the O’Connell effect,usually attributed to *** discuss the inclusion of.s.arspots in light curve solutions and how they influence the geometric and absolute parameters.

关键词： (stars)binaries eclipsing-techniques photometric-stars chromospheres

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao Michael s.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of.s.bstrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of.s.bstrate cleavage byγ-*** this review,we focus on recent studies of.s.ructural dynamic mechanisms ofγ-*** mechanisms,including the“fit-stay-Trim,”“sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of.s.bstrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

Dynamic and electrical responses of a curved sandwich beam with glass reinforced laminate layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 155-178页

作者： N.sHAHVEIsI s.fELI Department of Mechanical Engineering Razi UniversityKermanshah ***Iran

The dynamic responses and generated voltage in a curved sandwich beam with glass reinforced laminate(GRL)layers and a pliable core in the presence of a piezoelectric layer under low-velocity impact(LVI)are *** current study aims to carry out a dynamic analysis on the sandwich beam when the impactor hits the top face sheet with an initial *** the layer analysis,the high-order shear deformation theory(HsDT)and frostig's second model for the displacement fields of the core layer are *** classical non-adhesive elastic contact theory and Hunter's principle are used to calculate the dynamic responses in terms of *** order to validate the analytical method,the outcomes of the current investigation are compared with those gained by the experimental tests carried out by other researchers for a rectangular composite plate subject to the *** element(fE)simulations are conducted by means of the ABAQUs *** effects of the parameters such as foam modulus,layer material,fiber angle,impactor mass,and its velocity on the generated voltage are reviewed.

关键词： analytical model piezoelectric layer curved sandwich beam glass reinforced laminate(GRL) pliable core low-velocity impact(LVI) classical non-adhesive elastic contact theory

MXenes for Bioinspired soft Actuators:Advancements in Angle-Independent structural Colors and Beyond

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Nano-Micro Letters 2024年第8期16卷 18-34页

作者： siavash Iravani Rajender s.Varma Independent Researcher W Nazar STBoostan AveIsfahanIran Centre of Excellence for Research in sustainable Chemistry Department of ChemistryFederal University of São CarlosSão CarlosSP 13565‑905Brazil

soft actuators have garnered substantial attention in current years in view of their potential appliances in diverse domains like robotics,biomedical devices,and biomimetic *** actuators mimic the natural movements of living organisms,aiming to attain enhanced flexibility,adaptability,and *** the other hand,angle-independent structural color has been achieved through innovative design strategies and engineering *** carefully controlling the size,shape,and arrangement of nanostructures,researchers have been able to create materials exhibiting consistent colors regardless of the viewing *** promising class of materials that holds great potential for bioinspired soft actuators is MXenes in view of their exceptional mechanical,electrical,and optical *** integration of MXenes for bioinspired soft actuators with angle-independent structural color offers exciting *** material compatibility issues,improving color reproducibility,scalability,durability,power supply efficiency,and cost-effectiveness will play vital roles in advancing these *** perspective appraises the development of bioinspired MXene-centered soft actuators with angleindependent structural color in soft robotics.

关键词： MXenes MXene-based composites Bioinspired soft robotics Angle-independent structural color

New evidence for the epigenetic regulation of.s.eletal stem cells

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science Bulletin 2024年第13期69卷 2004-2006页

作者： Liming Zhao Jun Xiao Charles K.f.Chan Institute for stem Cell Biology and Regenerative Medicine Stanford University School of MedicineStanford CA 94305USA Department of.s.rgery Division of Plastic and Reconstructive SurgeryStanford University School of MedicineStanford CA 94305USA Department of Orthopaedic surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

skeletal stem cells(ssCs)are crucial for skeletal development and regeneration,yet the epigenetic regulation of these cells remains poorly *** studies have delineated the epigenetic landscape across the developmental trajectory of.s.Cs,highlighting the involvement of Ptip in regulating ssC *** skeletal system undergoes dynamic remodeling throughout *** stem cells(ssCs),residing within the skeleton and lineage-restricted,serve as a cellular reserve to f.s.er development and maintain skeletal *** categorized within the broader mesenchymal stromal/stem cells(MsCs).

关键词： skeletal involvement maintain

Tensor force impact on shell evolution in neutron-rich si and Ni isotopes

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Chinese Physics C 2024年第4期48卷 95-106页

作者： s.V.sidorov A.s.Kornilova T.Yu.Tretyakova faculty of Physics Lomonosov Moscow State UniversityMoscow 119991Russia skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State UniversityMoscow 119991Russia

The influence of the tensor interaction of nucleons on the characteristics of neutron-rich silicon and nickel isotopes was studied in this *** forces are considered within the framework of the Hartree-fock approach with the skyrme *** addition of a tensor component of interaction is shown to improve the description of the splittings between different single-particle states and decrease nucleon-nucleon pairing correlations in silicon and nickel *** attention was directed toward the role of isovector tensor forces relevant to the interaction of like nucleons.

关键词： nuclear shell model tensor interaction silicon isotopes nickel isotopes