Peierls ground state and excitations in the electron-lattice correlated system (EDO-TTF)_2X

We investigate the exotic Peierls state in the one-dimensional organic compound (EDO-TTF)_2X, wherein the Peierls transition is accompanied by the bending of molecules and also by a fourfold periodic array of charge disproportionation along the one-dimensional chain. Such a Peierls state, wherein the interplay between the electron correlation and the electron-phonon interaction takes an important role, is examined based on an extended Peierls–Holstein–Hubbard model that includes the alternation of the elastic energies for both the lattice distortion and the molecular deformation. The model reproduces the experimentally observed pattern of the charge disproportionation and there exists a metastable state wherein the energy takes a local minimum with respect to the lattice distortion and/or molecular deformation. Furthermore, we investigate the excited states for both the Peierls ground state and the metastable state by considering the soliton formation of electrons. It is shown that the soliton excitation from the metastable state costs energy that is much smaller than that of the Peierls state, where the former is followed only by the charge degree of freedom and the latter is followed by that of spin and charge. Based on these results, we discuss the exotic photoinduced phase found in (EDO-TTF)_2PF_6.journal articl

Upper Bound on the Decay τ→μγ from the Belle Detector

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GENERAL THREE-DIMENSIONAL COMPLEX FUNCTION THEORY. II.

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A Method Of Estimation Of Elastic Properties And Thicknesses Of Soil Layers Using Vertical Harmonic Loading On Ground Surface And Its Numerical Verification

This paper presents a new method that may achieve a more accurate and lower cost estimation of elastic properties and thicknesses of soil deposits. The kernel of the proposed method, being independent of the usually adopted assumption that only one Rayleigh wave model is dominant, is to use the near field characteristics of all types of P-SV wave motions on the surface of elastic multi-layered half space generated by the vertical harmonic load applied on its surface. The near field wave motions are accurately simulated by the stiffness matrix method as one of more powerful numerical solutions, and then the following two physical quantities, which can be observable in the field, are used in inversion analysis: （1） the predominant frequency for which the dynamic vertical displacement on the soil surface takes a maximum value, and （2） the frequency variation of the phase velocity at a point on the soil surface near the vertical harmonic load. The phase velocity used in the proposed method is a local quantity varying with the location from the vertical load, because of using all types of waves and their modes. To demonstrate the capability and reliability of the proposed method, the numerical examples are presented by using regular and irregular soil profiles

Simulation of PC to DCN synaptic conductance.

<p>(A) Saturating level of release probability (Rss) taken from Pedroarena and Schwarz (2003) could be modeled with a double exponential function (red line, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000485#s2" target="_blank">Materials and Methods</a> for details). (B) Simulated synaptic conductance profiles in response to 10, 30 and 100 Hz PC firing, respectively. These results should be compared to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0000485#pone-0000485-g007" target="_blank">Figure 7A</a> of Pedroarena and Schwarz (2003).</p

Summary of spontaneous simple spike firing properties of all PCs reported in this study.

<p>p: comparison to anesthetized rats, p^*: comparison to awake mice, Student t test.</p

Regular patterns in cerebellar Purkinje cell simple spike trains.

<p>(A) Raster plot of PC SS in an anesthetized rat (AnR). (B) CV₂ distributions of SS trains recorded from anesthetized mice (AnM, left), awake mice (AwM, middle, blue: neurons in cerebral motor cortex), and mean of 92 CV₂ distributions (Pooled, right) which were significantly different from those of inhomogeneous Poisson processes with similarly modulated firing rates (p<0.05, χ² test; *: p<0.001, χ² goodness of fit residual test; red line: CV₂ = 0.2). Insets and right panel: mean±s.e.m. (black: PC, green: inhomogeneous Poisson process) (C) Extracting regular spiking patterns by setting CV₂ threshold at 0.2 (white dotted lines). White dashes: CV₂ values calculated from the two surrounding ISIs, red: first ISI of regular patterns, pink: successive ISIs in regular patterns, dark blue: ISIs not belonging to a regular pattern).</p

Coincident patterns in nearby PC pairs in AnR.

<p>(A) Eight cross-correlograms of timings of spikes belonging to regular patterns extracted from recordings of nearby PC pairs, with each pair colored differently. Insets: cross-correlograms of the shuffled spike trains of two pairs (black) superimposed on original cross-correlogram of patterns (blue and gray: pairs showing strongest and weakest synchronization respectively). (B) The relation of pattern mean ISIs in 4 pairs in which pattern starts coincided significantly (inset: cross-correlograms of the first spikes of regular patterns in the 4 pairs). Red dotted line: diagonal.</p

Regular patterns and singles related to the membrane potential (MP).

<p>Dendritic patch-clamp recording of PC in anesthetized rat (data from Loewenstein et al. 2005). Voltage trace: large spikes are complex spikes, small ones are simple spikes. Dotted black line: threshold to define up and down-states (MP = −55 mV). Raster plot at top: simple spikes were sorted as either pattern spikes (dotted red lines: start of patterns, solid red lines: following spikes in each pattern) or single spikes (blue lines). All patterns were during up-state, but singles occurred both during up (filled circles) and down (open circles) states.</p

Simulated synaptic conductance in PC to DCN synapse caused by spontaneous PC spiking.

<p>(A) A representative example of the simulated synaptic conductance (G_syn) induced by PC (black) of AnR (upper panel), AnM (middle panel) and AwM (lower panel), and by corresponding realizations of an inhomogeneous Poisson process (green). Rasters: spikes belonging to patterns (black and green dotted lines: start of patterns, black and green solid lines: following spikes in patterns, blue lines: singles), numbers: number of all spikes in the 500 ms window. (B) Distribution of G_syn values for PCs (black) compared to Poisson processes (green). Bin = 0.2 nS. Red bar: bins where PCs contained significantly more G_syn values. p<0.05.</p