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941.
Vortex configurations on a thin superconducting spherical shell in the presence of a magnetic dipole
Leonardo R.E. Cabral J. Albino Aguiar 《Physica C: Superconductivity and its Applications》2010,470(19):796-798
In this work we study vortex configurations on a thin superconducting spherical shell of radius R and thickness d (R?d?ξ) with a magnetic dipole inside it. The point magnetic dipole (with magnetic moment, mz) is oriented along one of the sphere main axis. It is placed a distance z0 from the center of the sphere. Due to the symmetry of the sample, there are vortices and antivortices pancakes on the shell resulting in zero total vorticity. The vortex interactions with the shielding currents produced by the external fields – as well as with other vortices – are calculated within the London limit. The vortex configurations are obtained by solving numerically the Bardeen–Stephen equation of motion for the vortices. For z0≈0 the most frequent vortex configurations present equal arrangements of vortices and antivortices on the north and south hemispheres. For z0≈0.5R, the diversity of vortex configurations increases, with a higher number of configurations (in comparison to smaller z0) having different vortices and antivortices distributions on each shell hemisphere. We also study the equilibrium states dependence on the magnetic dipole strength and position. 相似文献
942.
Leonardo M. Elias 《Optimization》2016,65(4):751-763
We present two generalized conjugation schemes for lower semi-continuous functions defined on a real Banach space whose norm is Fréchet differentiable off the origin, and sketch their applications to optimization duality theory. Both approaches are based upon a new characterization of lower semi-continuous functions as pointwise suprema of a special class of continuous functions. 相似文献
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Leonardo Ermann Klaus M. Frahm Dima L. Shepelyansky 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(6):127
We construct and study the Google matrix of Bitcoin transactions during the time period from the very beginning in 2009 till April 2013. The Bitcoin network has up to a few millions of bitcoin users and we present its main characteristics including the PageRank and CheiRank probability distributions, the spectrum of eigenvalues of Google matrix and related eigenvectors. We find that the spectrum has an unusual circle-type structure which we attribute to existing hidden communities of nodes linked between their members. We show that the Gini coefficient of the transactions for the whole period is close to unity showing that the main part of wealth of the network is captured by a small fraction of users. In global the Google matrix analysis of bitcoin network gives a new understanding of the bitcoin transactions with PageRank and CheiRank characterization of sellers and buyers which are dominant not simply due to the sold/bought volume but also by taking into account if bitcoins are sold to (bought by) other important sellers (buyers). 相似文献
946.
Leo Li-Ying Chan Jianping Huang Yusuke Hagiwara Leonardo Aguila David Rowe 《Journal of fluorescence》2014,24(4):1041-1053
Flow cytometry has become a standard tool for defining a heterogeneous cell population based on surface expressed epitopes or GFP reporters that reflect cell types or cellular differentiation. The introduction of image cytometry raised the possibility of adaptation to discriminate GFP reporters used to appreciate cell heterogeneity within the skeletal lineages. The optical filters and LEDs were optimized for the reporters used in transgenic mice expressing various fluorescent proteins. In addition, the need for compensation between eGFP and surrounding reporters due to optical cross-talk was eliminated by selecting the appropriate excitation and emission filters. Bone marrow or articular cartilage cell cultures from GFP and RFP reporter mouse lines were established to demonstrate the equivalency in functionalities of image to flow cytometry analysis. To examine the ability for monitoring primary cell differentiation, articular chondrocyte cell cultures were established from mice that were single or doubly transgenic (Dkk3eGFP and Col2A1GFPcyan), which identify the progression of superficial small articular cell to a mature chondrocyte. The instrument was able to rapidly and accurately discriminate cells that were Dkk3eGFP only, Dkk3eGFP/Col2A1GFPcyan, and Col2A1GFP, which provides a useful tool for studying the impact of culture conditions on lineage expansion and differentiation. 相似文献
947.
Physics of Atomic Nuclei - The studies of the production of the X(3872), either prompt or from B-hadron decays, and of the J/ψϕ mass spectrum in B-hadron decays have been carried out by... 相似文献
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949.
Jéssica Maria de Souza Bruno Rodrigues Fazolo Jhully Wellen Ferreira Lacerda Mariana de Souza Moura Arielly Celestino Rodrigues dos Santos Leonardo Gomes de Vasconcelos Paulo Teixeira de Sousa Junior Evandro Luiz Dall’Oglio Akbar Ali Olívia Moreira Sampaio Lucas Campos Curcino Vieira 《Photochemistry and photobiology》2020,96(6):1233-1242
We report the synthesis of twelve indole derivatives bearing nitro or amide groups via Fischer indole methodology followed by reduction/acetylation and amidation reactions. After thorough characterization, these indoles were subjected to a number of studies in order to evaluate their bioactive potential as photosynthesis and plant growth inhibitors. Firstly, these molecular hybrids were evaluated as photosystem II (PSII) inhibitors through chlorophyll a (Chl a) fluorescence measurement. In this study, 6-chloro-8-nitro-2,3,4,9-tetrahydro-1H-carbazole ( 15a ) and 5-chloro-2,3-dimethyl-7-nitro-1H-indole ( 15b ) showed the best results by reducing the phenomenological parameters of reaction centers ABS/RC, TR0/RC and ET0/RC of PSII. Electron chain blockage by these compounds may lead to diminished ATP synthesis and CO2 fixation which interrupt the plant development. The compounds 15a and 15b both act as postemergent herbicides, reducing the dry biomass of Ipomoea grandifolia and Senna alata weeds by an average of 40% and 37%, respectively, corroborating the fluorescence results. Additionally, the molecular docking study revealed that the presence of strong electron-withdrawing groups at the indole phenyl ring is important for the ligand’s interaction with the binding pocket of protein D1 on PSII. The optimization of these molecular features is the goal of our research group in further understanding and development of new potent herbicides. 相似文献
950.
Two new non-parametric tests are proposed based on continuous one-dimensional random projections. The first one addresses central symmetry and the second addresses independence. These tests are implemented for finite and infinite dimensional (functional) data sets. Both tests are distribution-free and universally consistent. Additionally, different techniques are proposed to improve the power of the tests. Promising results have been obtained by comparing the new tests with existing ones using simulation study. Real data in Banach spaces have been used to develop an application. 相似文献