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81.
82.
Michele Mugnaine Adriane S. Reis Fernando S. Borges Rafael R. Borges Fabiano A. S. Ferrari Kelly C. Iarosz Ibere L. Caldas Ewandson L. Lameu Ricardo L. Viana Jose D. SzezechJr. Jürgen Kurths Antonio M. Batista 《The European physical journal. Special topics》2018,227(10-11):1151-1160
The human cerebral cortex can be separated into cortical areas forming a clustered network structure. We build two different clustered networks, where one network is based on a healthy brain and the other according to a brain affected by a neurodegenerative process. Each cortical area has a subnetwork with small-world properties. We verify that both networks exhibit rich-club organisation and phase synchronisation. Due to the fact that neuronal synchronisation can be related to brain diseases, we consider the delayed feedback control as a method to suppress synchronous behaviours. In this work, it is presented that depending on the feedback parameters, intensity and time delay, phase synchronisation in both networks can be suppressed. Therefore, one of our main results is to show that delayed feedback control can be used to suppress undesired synchronous behaviours not only in the healthy brain, but also in the brain marked by neurodegenerative processes. 相似文献
83.
Borges L. H. C. Barone F. A. Helayël-Neto J. A. 《The European Physical Journal C - Particles and Fields》2014,74(6):1-7
The present work is a generalization of the recent work [arXiv.1206.1420] on the modified Hawking temperature on the event horizon. Here the Hawking temperature is generalized by multiplying the modified Hawking temperature by a variable parameter \(\alpha \) representing the ratio of the growth rate of the apparent horizon to that of event horizon. It is found that both the first and the generalized second law of thermodynamics are valid on the event horizon for any fluid distribution. Subsequently, the Bekenstein entropy is modified on the event horizon and the thermodynamical laws are examined. Finally, an interpretation of the parameters involved is presented. 相似文献
84.
85.
J.S. Alcaniz H.A. Borges S. Carneiro J.C. Fabris C. Pigozzo W. Zimdahl 《Physics letters. [Part B]》2012
We demonstrate that creation of dark-matter particles at a constant rate implies the existence of a cosmological term that decays linearly with the Hubble rate. We discuss the cosmological model that arises in this context and test it against observations of the first acoustic peak in the cosmic microwave background (CMB) anisotropy spectrum, the Hubble diagram for supernovas of type Ia (SNIa), the distance scale of baryonic acoustic oscillations (BAO) and the distribution of large scale structures (LSS). We show that a good concordance is obtained, albeit with a higher value of the present matter abundance than in the ΛCDM model. We also comment on general features of the CMB anisotropy spectrum and on the cosmic coincidence problem. 相似文献
86.
Margarida S. Miranda José E. Rodríguez‐Borges Joaquim C. G. Esteves da Silva Xerardo García‐Mera 《Journal of Physical Organic Chemistry》2012,25(6):515-522
The cycloaddition between glyoxylate imines possessing two chiral auxiliaries, N‐(R)‐ or N‐(S)‐1‐phenylethyl and 8‐phenylmenthyl or 8‐phenylneomenthyl, and cyclopentadiene is described. Computational calculations using density functional theory with the Becke, three‐parameter, Lee–Yang–Parr functional and the 6‐31G(d) basis set were performed to better understand the highly diastereoselective mechanism and the exo‐selectivity observed experimentally for these ionic aza‐Diels–Alder reactions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
87.
João Eduardo Borges Nuno H. C. Pereira Jorge Matos Kathleen H. Frizell 《Experiments in fluids》2010,48(1):17-31
The development of a three-hole pressure probe with back-flushing combined with a conductivity probe, used for measuring simultaneously
the magnitude and direction of the velocity vector in complex air–water flows, is described in this paper. The air–water flows
envisaged in the current work are typically those occurring around the rotors of impulse hydraulic turbines (like the Pelton
and Cross-Flow turbines), where the flow direction is not known prior to the data acquisition. The calibration of both the
conductivity and three-hole pressure components of the combined probe in a rig built for the purpose, where the probe was
placed in a position similar to that adopted for the flow measurements, will be reported. After concluding the calibration
procedure, the probe was utilized in the outside region of a Cross-Flow turbine rotor. The experimental results obtained in
the present study illustrate the satisfactory performance of the combined probe, and are encouraging toward its use for characterizing
the velocity field of other complex air–water flows. 相似文献
88.
The on‐line quality monitoring procedure for attributes proposed by Taguchi, Elsayed and Hsiang for processes in which the fraction defective shifts from 0 at some point are examined under the assumption of diagnosis errors. The renewal reward (economic) approach of Nayebpour and Woodall is used to develop a mathematical expression for the long‐run expected cost per item produced and assessment of the optimum inspection interval is discussed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
89.
CM Silva MF Duarte ML Mira MH Florêncio K Versluis AJ Heck 《Rapid communications in mass spectrometry : RCM》1999,13(12):1098-1103
Fast atom bombardment, combined with high-energy collision-induced tandem mass spectrometry, has been used to investigate gas-phase metal-ion interactions with captopril, enalaprilat and lisinopril, all angiotensin-converting enzyme inhibitors.Suggestions for the location of metal-binding sites are presented. For captopril, metal binding occurs most likely at both the sulphur and the nitrogen atom. For enalaprilat and lisinopril, binding preferably occurs at the amine nitrogen. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
90.
M.A. Continentino J.C. Fernandes R.B. Guimar aes H.A. Borges A. Sulpice J.-L. Tholence J.L. Siqueira J.B.M. da Cunha C.A. dos Santos 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,9(4):613-618
The system Cu2FeO2BO3 is an oxyborate belonging to the family of the ludwigites. In this paper we present AC susceptibility, magnetization measurements
and M?ssbauer spectroscopy on this material which allows for a complete characterization of its complex magnetic behavior.
We find an hierarchy of interactions which clearly defines three regimes with decreasing temperature. These are associated
with, the freezing of the Fe moments, the antiferromagnetic ordering of the Cu sub-lattice and finally the coupling between
both systems.
Received 25 September 1998 相似文献