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Recent results on nucleon resonance electrocouplings from the studies of π^+π^-p electroproduction with the ClAS detector

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Chinese Physics C 2009年第12期33卷 1210-1215页

作者： V. I. Mokeev V. D. burkert l. Elouadrhiri g. V. Fedotov E. n. golovach b. S. Ishkhanov Jefferson lab Newport News 12000 Jefferson Ave VA 23606 USA Skobeltsyn nuclear Physics Institute at Moscow State University Moscow 119899 Russia Physics Department at Moscow State University Moscow 119899 Russia

Recent results on nucleon resonance studies in π＋π-p electro- production off protons with the ClAS detector are presented. The analysis of ClAS data allowed us to determine all essential contributiag mechanisms, providing a credible separation between resonant and non-resonant parts of the cross sections in a wide kinematical area of invariant masses of the final hadronic system 1.3 〈 W 〈 1.8 geV and photon virtutualities 0.2 〈 Q2 〈 1.5 geV2. Electrocouplings of several excited proton states with masses less than 1.8 geV were obtained for the first time from the analysis of π＋π-p exclusive electroproduction channel.

关键词： nucleon resonances electromagnetic form factors nucleon structure

Structural and mass transport properties of liquid ytterbium in the temperature range 1123 K–1473 K

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Chinese Physics b 2023年第6期32卷 481-488页

作者： D D Satikunvar n K bhatt b Y Thakore Department of Physics Sardar Patel UniversityVallabh VidyanagarGujarat 388120India Department of Physics Maharaja Krishnakumarsinhji Bhavnagar UniversityBhavnagarGujarat 364001India

We have studied the structural and atomic transport properties of liquid f-shell Yb in the temperature range 1123 K–1473 K. Pair interactions between atoms are derived using a local pseudopotential. The potential parameters are fitted to the phonon dispersion curve at room temperature. The local pseudopotential used in the present study is computationally more efficient with only three parameters, and it is found to be transferable to the liquid phase without changing the *** the various computed properties agree with reported theoretical and experimental findings, the adopted fitting scheme is justified. As a significant outcome of the study, we find that(i) the melting in Yb is governed by the lindemann's law,(ii)the mass transport mechanism obeys the Arrhenius law,(iii) the role of the three-particle correlation function in deriving the velocity autocorrelation function is small,(iv) the mean-square atomic displacement is more sensitive to the choice of interaction potential than the other bulk properties, and(v) liquid Yb does not show liquid–liquid phase transition within the studied temperature range. Further, due to the good description of the structural and mass transport properties, we propose that Yb remains divalent at reduced density.

关键词： transport properties pseudopotential single-particle dynamics ytterbium

Structural and molecular features of intestinal strictures in rats with Crohn's-like disease

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World Journal of gastroenterology 2016年第22期22卷 5154-5164页

作者： Petra Talapka Anikó berkó lajos István nagy lalitha Chandrakumar Mária bagyánszki lászló géza Puskás éva Fekete nikolett bódi Department of Physiology Anatomy and Neuroscience Faculty of Sciences and Informatics University of Szeged H-6726 Szeged Hungary Avidin ltd. H-6726 Szeged Hungary

AIM: To develop a new rat model we wanted to gain a better understanding of stricture formation in Crohn’s disease (CD).METHODS: Chronic colitis was induced locally by the administration of 2,4,6-trinitrobenzenesulfonic acid (TnbS). The relapsing inflammation characteristic to CD was mimicked by repeated TnbS treatments. Animals were randomly divided into control, once, twice and three times TnbS-treated groups. Control animals received an enema of saline. Tissue samples were taken from the strictured colonic segments and also adjacent proximally and distally to its 60, 90 or 120 d after the last TnbS or saline administrations. The frequency and macroscopic extent of the strictures were measured on digital photographs. The structural features of strictured gut wall were studied by light- and electron microscopy. Inflammation related alterations in TgF-beta 2 and 3, matrix metalloproteinases 9 (MMP9) and TIMP1 mRnA and protein expression were determined by quantitative real-time PCR and western blot analysis. The quantitative distribution of caspase 9 was determined by post-embedding ***: Intestinal strictures first appeared 60 d after TnbS treatments and the frequency of them increased up to day 120. From day 90 an intact lamina epithelialis, reversible thickening of lamina muscularis mucosae and irreversible thickening of the muscularis externa were demonstrated in the strictured colonic segments. nevertheless the morphological signs of apoptosis were frequently seen and excess extracellular matrix deposition was recorded between smooth muscle cells (SMCs). Enhanced caspase 9 expression on day 90 in the SMCs and on day 120 also in myenteric neurons indicated the induction of apoptosis. The mRnA expression profile of TgF-betas after repeated TnbS doses was characteristic to CD, TgF-beta 2, but not TgF-beta 3 was up-regulated. Overexpression of MMP9 and down-regulation of TIMP1 were demonstrated. The progressive increase in the amount

关键词： Crohn’ s disease Rat model TgF-beta Intestinal strictures MMP9 TIMP1

Tonalites and plagiogranites of the Char suture-shear zone in East Kazakhstan:Implications for the Kazakhstan-Siberia collision

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geoscience Frontiers 2016年第1期7卷 141-150页

作者： M.l.Kuibida I.Yu.Safonova P.V.Yermolov A.g.Vladimirov n.n.Kruk S.Yamamoto lnstitute of geology and Mineralogy Sb RAS Koptyuga ave.3Novosibirsk630090Russia novosibirsk State University Pirogova St.2Novosibirsk630090Russia IPCOn Joint Venture Academy of Sciences of Kazakhstanlppodromnaya 5100019KaragandaKazakhstan Tomsk State University Lenina St.36Tomsk634050Russia University of Tokyo MeguroTokyo153-8902Japan

The paper presents first Ue Pb zircon ages and geochemical data from Carboniferous granitoids（tonalites and plagiogranites） of the Char sutureeshear zone in East Kazakhstan, which is located in the northwestern Central Asian Orogenic belt（CAOb）. The study included analysis of geological setting, major and trace elements, and rock petrogenesis. The Char tonalites and plagiogranites occur as nW-striking linear chains inside Visean serpentinite mélange. Petrographycally, the tonalites show signs of syntectonic deformation, and the plagiogranites are less deformed suggesting their later intrusion. The tonalites yielded a lA-ICP-MS zircon age of ca. 323 Ma, i.e. exactly at the boundary between the early and late Carboniferous. Compositionally, the tonalites and plagiogranites are characterized, respectively, by high SiO2（67-70 and 73-74 wt.%） and Al2O3（17-19 and 14-15 wt.%）, Sr/Y 〉 40 and low Yb=0.2-0.5 *** multi-element patterns show clear nb-Ta negative anomalies. The low nb/Ta ratios（7-15） and Zr（114-191 ppm） suggest a MORb-type protolith（amphibolite） with subchondritic nb/Ta（8-17） and low Zr（1-72 ppm）. The low contents of K and Rb suggest weak assimilation of the melts by island arc felsic crust. The subchondritic nb/Ta ratios exclude their derivation by the melting of subducted/dehydrated MORb. We argue that the Char high-Al tonalites and plagiogranites formed by the melting of hydrated MORb at the base of the mafic lower crust at pressures of 10-15 kbar. The occurrences of the Char tonalites and plagiogranites inside the Visean serpentinite mélange overlapped by Serpukhovian conglomerates, their alignment parallel to deformation zones, and their geochemical features suggest their origin by the melting of mafic lower crust in relation to the collision of the Siberian and Kazakhstan continents.

关键词： Earlyelate Carboniferous boundary nW Central Asian Orogenic belt U-Pb ages Whole-rock geochemistry Petrogenesis Mafic crust melting

Hadron resonances as rovibrational states

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Chinese Physics C 2021年第8期45卷 99-104页

作者： Douglas l.bernardo Cristiano C.bastos Antonio C.pavao Departamento de Quimica Fundamental Universidade Federal de PernambucoRecife50740-540Brazil Departamento de Quimica Universidade Federal Rural de PernambucoRecife52171-900Brazil

A rovibrational model,including anharmonic,centrifugal,and Coriolis corrections,is used to calculate π,K,n,and ∑ orbital and radial *** four orbital excitations of the n meson correspond to the/?(1235),ti2(1670),63(2030),and π4(2250)*** first four radial excitations correspond to the π(1300),π(1800),π(2070),and 7t(2360)*** orbital excitations of the K meson are interpreted as the K_(1)(1270),K_(2)(1770),K_(3)(2320),and K_(4)(2500)resonances;its radial excitations correspond to the K(1460)and K(1830)*** n orbital excitations are identified with the n(1520),n(1680),n(2190),n(2220),and n(2600)*** first four radial excitations of the n family correspond to the n(1440),n(1880),n(2100),and n(2300)*** orbital excitations of the ∑ baryon are associated with the ∑(1670),∑(1915),∑(2100),and ∑(2250)resonances,whereas its radial excitations are identified with the ∑(1660),∑(1770),and ∑(1880)*** proposed rovibrational model calculations show a good agreement with the corresponding experimental values and allow for the prediction of hadron resonances,thereby proving to be useful for the interpretation of excited hadron spectra.

关键词： excited hadron spectrum orbital and radial resonances rovibrational states

Monitoring and characterization of particle contamination in the pulse compression chamber of the OMEgA EP laser system

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High Power laser Science and Engineering 2023年第3期11卷 64-72页

作者： b.n.Hoffman n.Savidis S.g.Demos laboratory for laser Energetics University of RochesterRochesterNew YorkUSA

The laser-damage performance of optics is known to be negatively affected by microscale particle contamination induced by the operational *** work investigates the properties of particles accumulating in various locations near critical optics inside the OMEgA EP grating compressor chamber during quarterly operational periods over a 2-year *** particles found were characterized using optical microscopy,scanning electron microscopy and energy dispersive X-ray *** analysis indicates significant concentrations of micrometer-to nanometerscale particles inside the vacuum chamber,with higher values observed near the port leading to the OMEgA EP target *** distribution of the chemical composition of these particles varies between collection *** understanding of the mechanisms of particle generation and transport remains uncertain,the hypothesis is that this particle load represents a risk for contaminating the surfaces of high-value optics located inside the chamber,including the compression gratings and deformable mirrors,and therefore affecting their laser-damage resistance and overall operational lifetime.

关键词： laser damage particle contamination

Heat transfer and entropy generation analysis of non-newtonian fluid flow through vertical microchannel with convective boundary condition

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Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1285-1300页

作者： M. MADHU n. S. SHASHIKUMAR b. MAHAnTHESH b. J. gIREESHA n. KISHAn Department of Studies and Research in Mathematics Kuvempu University Shankaraghatta 577451 India Department of Mathematics Christ Deemed to be University Bangalore 560029 India Department of Mathematics Osmania University Telangana 500007 India

The entropy generation and heat transfer characteristics of magnetohydrodynamic (MHD) third-grade fluid flow through a vertical porous microchannel with a convective boundary condition are analyzed. Entropy generation due to flow of MHD non-newtonian third-grade fluid within a microchannel and temperature-dependent viscosity is studied using the entropy generation rate and Vogel's model. The equations describing flow and heat transport along with boundary conditions are first made dimensionless using proper non-dimensional transformations and then solved numerically via the finite element method (FEM). An appropriate comparison is made with the previously published results in the literature as a limiting case of the considered problem. The comparison confirms excellent agreement. The effects of the grashof number, the Hartmann number, the biot number, the exponential space-and thermal-dependent heat source (ESHS/THS) parameters, and the viscous dissipation parameter on the temperature and velocity are studied and presented graphically. The entropy generation and the bejan number are also calculated. From the comprehensive parametric study, it is recognized that the production of entropy can be improved with convective heating and viscous dissipation aspects. It is also found that the ESHS aspect dominates the THS aspect.

关键词： microchannel entropy generation bejan number third-grade fluid magnetic field

Imperative Dynamic Routing between Capsules network for Malaria Classification

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Computers, Materials & Continua 2021年第7期68卷 903-919页

作者： g.Madhu A.govardhan b.Sunil Srinivas Kshira Sagar Sahoo n.Z.Jhanjhi K.S.Vardhan b.Rohit Department of Information Technology VNRVJIETHyderabad500090India Department of Computer Science and Engineering JNTUH College of EngineeringHyderabadIndia Department of Computer Science and Engineering TKR College of Engineering&TechnologyHyderabadIndia Department of Computer Science and Engineering SRM UniversityAmaravatiA.P.522502India School of Computer Science and Engineering Taylor’s UniversitySubang Jaya47500Malaysia Department of Computer Science and Engineering VNRVJIETHyderabad500090India

Malaria is a severe epidemic disease caused by Plasmodium *** parasite causes critical illness if persisted for longer durations and delay in precise treatment can lead to further *** automatic diagnostic model provides aid for medical practitioners to avail a fast and efficient *** of the existing work either utilizes a fully connected convolution neural network with successive pooling layers which causes loss of information in ***,convolutions can capture spatial invariances but,cannot capture rotational *** to overcome these limitations,this research,develops an Imperative Dynamic routing mechanism with fully trained capsule networks for malaria *** model identifies the presence of malaria parasites by classifying thin blood smears containing samples of parasitized and healthy *** proposed model is compared and evaluated with novel machine vision models evolved over a decade such as Vgg,Resnet,Densenet,*** problems in previous research are cautiously addressed and overhauled using the proposed capsule network by attaining the highest Area under the curve(AUC)and Specificity of 99.03%and 99.43%respectively for 20%test *** understand the underlying behavior of the proposed network various tests are conducted for variant shuffle *** model is analyzed and assessed in distinct environments to depict its resilience and *** provide greater generalization,the proposed network has been tested on thick blood smear images which surpassed with greater performance.

关键词： Dynamic routing deep neural networks thin blood smears computer vision parasite classification

Multilevel atomic Ramsey interferometry for precise parameter estimations

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Chinese Physics b 2021年第12期30卷 321-328页

作者： X n Feng l F Wei guangdong Provincial Key laboratory of Quantum Metrology and Sensing&School of Physics and Astronomy Sun Yat-Sen University(Zhuhai Campus)Zhuhai 519082China Information Quantum Technology laboratory School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China

Multi-path(or multi-mode)entanglement has been proved to be a useful resource for sub-shot-noise sensitivity of phase estimation,which has aroused much research interest in quantum metrology *** schemes of multi-path interferometers based on optical systems have been put ***,we study a multi-state interferometer with multilevel atoms by projective ***,we investigate its ultimate sensitivity described by quantum Fisher information theory and find that the Cramer-Rao bound can be *** particular,we investigate a specific scheme to improve the sensitivity of magnetometery with a three-state interferometry delivered by a single nitrogen-vacancy(nV)center of diamond with tailor *** impacts of imperfections of the atomic beam-splitter,described by the three-level quantum Fourier transform,on the sensitivity of phase estimation is also discussed.

关键词： quantum metrology multi-path interferometers quantum measurement