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361.
Fabrizio Esposito Adriana Aragri Tommaso Piccoli Gioacchino Tedeschi Rainer Goebel Francesco Di Salle 《Magnetic resonance imaging》2009
Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) represent brain activity in terms of a reliable anatomical localization and a detailed temporal evolution of neural signals. Simultaneous EEG-fMRI recordings offer the possibility to greatly enrich the significance and the interpretation of the single modality results because the same neural processes are observed from the same brain at the same time. Nonetheless, the different physical nature of the measured signals by the two techniques renders the coupling not always straightforward, especially in cognitive experiments where spatially localized and distributed effects coexist and evolve temporally at different temporal scales. 相似文献
362.
Maruthibabu Paidikondala Vignesh Kumar Rangasami Ganesh N. Nawale Tommaso Casalini Giuseppe Perale Sandeep Kadekar Gaurav Mohanty Turkka Salminen Oommen P. Oommen Oommen P. Varghese 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(9):2841-2845
Circulating nucleic acids, such as short interfering RNA (siRNA), regulate many biological processes; however, the mechanism by which these molecules enter the cell is poorly understood. The role of extracellular‐matrix‐derived polymers in binding siRNAs and trafficking them across the plasma membrane is reported. Thermal melting, dynamic light scattering, scanning electron microscopy, and computational analysis indicate that hyaluronic acid can stabilize siRNA via hydrogen bonding and Van der Waals interactions. This stabilization facilitated HA size‐ and concentration‐dependent gene silencing in a CD44‐positive human osteosarcoma cell line (MG‐63) and in human mesenchymal stromal cells (hMSCs). This native HA‐based siRNA transfection represents the first report on an anionic, non‐viral delivery method that resulted in approximately 60 % gene knockdown in both cell types tested, which correlated with a reduction in translation levels. 相似文献
363.
M. I. Mazuritskiy A. M. Lerer A. Marcelli S. B. Dabagov M. Coreno A. D’Elia 《JETP Letters》2018,107(10):600-605
The diffraction of long-wavelength X rays with the energy corresponding to the region of anomalous dispersion near the Si L2,3 absorption edges transmitted through microchannel plates has been studied both experimentally and theoretically. The radiation of a finite antenna array, as well as the processes of excitation of X-ray fluorescence and propagation of waves in hollow waveguide structures, has been mathematically simulated. The model describes a polycapillary structure consisting of noninteracting emitters, which are hollow channels of a microchannel plate. It has been shown that coherently excited X-ray fluorescence propagates primarily in the direction of the zeroth diffraction order. 相似文献
364.
Tommaso de Fernex 《Transactions of the American Mathematical Society》2006,358(8):3717-3731
Let be an -dimensional regular local ring, essentially of finite type over a field of characteristic zero. Given an -primary ideal of , the relationship between the singularities of the scheme defined by and those defined by the multiplier ideals , with varying in , are quantified in this paper by showing that the Samuel multiplicity of satisfies whenever . This formula generalizes an inequality on log canonical thresholds previously obtained by Ein, Mustata and the author of this paper. A refined inequality is also shown to hold for small dimensions, and similar results valid for a generalization of test ideals in positive characteristics are presented.
365.
A bottom-up route towards the synthesis of titania nanosheets is explored, alternative to the exfoliation of layered titanates. Nanosheets are assembled from the constituent elements and epitaxially matched to a suitable substrate: (1 x 2)-Pt(110). Their basic lepidocrocite structure is modulated at the nanoscale due to coincidence with the substrate. Density functional calculations reveal the structure details of the nanosheet, which is also shown to be in close relationship with a (001)-oriented anatase bilayer. 相似文献
366.
N. Mironova-Ulmane U. Ulmanis A. Kuzmin I. Sildos M. Pärs M. Cestelli Guidi M. Piccinini A. Marcelli 《Physics of the Solid State》2008,50(9):1723-1726
The influence of dilution by diamagnetic ions on the magnetic ordering in single-crystal Co
c
Mg1−c
O solid solutions was studied by Raman spectroscopy and magneto-optical microscopy in a wide range of temperatures (6 < T < 200 K). Far infrared absorption measurements of antiferromagnetic resonance (AFMR) were also performed for pure CoO. It
was found that the domain structure and the contribution from Brillouin zone center magnons to Raman scattering and AFMR disappear
well below the Néel temperature, whose value was determined from neutron diffraction and magnetic susceptibility measurements.
The text was submitted by the authors in English. 相似文献
367.
Angelini L de Tommaso M Guido M Hu K Ivanov PCh Marinazzo D Nardulli G Nitti L Pellicoro M Pierro C Stramaglia S 《Physical review letters》2004,93(3):038103
We investigate phase synchronization in EEG recordings from migraine patients. We use the analytic signal technique, based on the Hilbert transform, and find that migraine brains are characterized by enhanced alpha band phase synchronization in the presence of visual stimuli. Our findings show that migraine patients have an overactive regulatory mechanism that renders them more sensitive to external stimuli. 相似文献
368.
369.
Sergio?Ortobelli?Lozza Tommaso?Lando Filomena?Petronio Tomá??TichyEmail author 《Methodology and Computing in Applied Probability》2016,18(4):1097-1115
We propose a multivariate stochastic dominance relation aimed at ranking different financial markets/sectors from the point of view of a non-satiable risk averse investor. In particular, we assume that the vector of returns of a given market is in the domain of attraction of a symmetric stable Paretian law in order to take into account the asymptotic behaviour of the financial returns. We determine the stochastic dominance rule for stable symmetric distributions, where the stability parameter plays a crucial role. Consequently, the multivariate rule for ordering markets is based on a comparison between i) location parameters, ii) dispersion parameters, and iii) stability indices. Finally, we apply the method to the equity markets of the four countries with the highest gross domestic product in 2013, namely, the US, China, Japan and Germany. In this empirical comparison we examine the ex ante and ex post dominance between stock markets, either assuming that the returns are jointly (or conditionally, for a robust approach) Gaussian distributed, or in the domain of attraction of a stable sub-Gaussian law. 相似文献
370.
Wolfgang P. Schleich Kedar S. Ranade Christian Anton Markus Arndt Markus Aspelmeyer Manfred Bayer Gunnar Berg Tommaso Calarco Harald Fuchs Elisabeth Giacobino Markus Grassl Peter Hänggi Wolfgang M. Heckl Ingolf-Volker Hertel Susana Huelga Fedor Jelezko Bernhard Keimer Jörg P. Kotthaus Gerd Leuchs Norbert Lütkenhaus Ueli Maurer Tilman Pfau Martin B. Plenio Ernst Maria Rasel Ortwin Renn Christine Silberhorn Jörg Schiedmayer Doris Schmitt-Landsiedel Kurt Schönhammer Alexey Ustinov Philip Walther Harald Weinfurter Emo Welzl Roland Wiesendanger Stefan Wolf Anton Zeilinger Peter Zoller 《Applied physics. B, Lasers and optics》2016,122(5):130