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Cognitive–behavioral therapy (CBT) is thought to be useful for chronic pain, with the pathology of the latter being closely associated with cognitive–emotional components. However, there are few resting-state functional magnetic resonance imaging (R-fMRI) studies. We used the independent component analysis method to examine neural changes after CBT and to assess whether brain regions predict treatment response.
We performed R-fMRI on a group of 29 chronic pain (somatoform pain disorder) patients and 30 age-matched healthy controls (T1). Patients were enrolled in a weekly 12-session group CBT (T2). We assessed selected regions of interest that exhibited differences in intrinsic connectivity network (ICN) connectivity strength between the patients and controls at T1, and compared T1 and T2. We also examined the correlations between treatment effects and rs-fMRI data.
Abnormal ICN connectivity of the orbitofrontal cortex (OFC) and inferior parietal lobule within the dorsal attention network (DAN) and of the paracentral lobule within the sensorimotor network in patients with chronic pain normalized after CBT. Higher ICN connectivity strength in the OFC indicated greater improvements in pain intensity. Furthermore, ICN connectivity strength in the dorsal posterior cingulate cortex (PCC) within the DAN at T1 was negatively correlated with CBT-related clinical improvements.
We conclude that the OFC is crucial for CBT-related improvement of pain intensity, and that the dorsal PCC activation at pretreatment also plays an important role in improvement of clinical symptoms via CBT.
It has been demonstrated that negatively distorted self-referential processing, in which individuals evaluate one's own self, is a pathogenic mechanism in subthreshold depression that has a considerable impact on the quality of life and carries an elevated risk of developing major depression. Behavioural activation (BA) is an effective intervention for depression, including subthreshold depression. However, brain mechanisms underlying BA are not fully understood. We sought to examine the effect of BA on neural activation during other perspective self-referential processing in subthreshold depression.
A total of 56 subjects underwent functional magnetic resonance imaging scans during a self-referential task with two viewpoints (self/other) and two emotional valences (positive/negative) on two occasions. Between scans, while the intervention group (n = 27) received BA therapy, the control group (n = 29) did not.
The intervention group showed improvement in depressive symptoms, increased activation in the dorsal medial prefrontal cortex (dmPFC), and increased reaction times during other perspective self-referential processing for positive words after the intervention. Also, there was a positive correlation between increased activation in the dmPFC and improvement of depressive symptoms. Additionally, there was a positive correlation between improvement of depressive symptoms and increased reaction times.
BA increased dmPFC activation during other perspective self-referential processing with improvement of depressive symptoms and increased reaction times which were associated with improvement of self-monitoring function. Our results suggest that BA improved depressive symptoms and objective monitoring function for subthreshold depression.
Electrical conductions in insulators such as resistance switching, conduction at interfaces, and conduction at domain boundaries and free surface of ferroelectrics are of interest. These conductions are often attributed to novel mechanism such as ferroelectric polarization. On the other hand, these interpretations appear not fully accepted, because the recent advanced theories of ferroelectric domains disregard screening indicated by these conduction phenomena. That is, these conduction phenomena are quietly regarded as the classical conduction originating from defects. In this paper, we examine these conductions in pure wide bandgap insulators in view of defects, using the direct-accessibility (tangibility) of conduction at free surfaces. Although most of these conductions in ferroelectrics may not be useful in large-scale applications, we show that they have fundamental implications on renovations of ferroelectric basics.
We present a comparative study of the anomalous Nernst effect (ANE), measured at room temperature for magnetite thin films deposited on different substrates in order to study the effects induced by the substrate, compressive or tensile strain and structural defects as anti-phase boundaries (APB), on the observed ANE. From our preliminary results we have observed an increase of the measured ANE in the case of compressive strain compared with the tensile one. Moreover our results also suggest that the density of APBs also play an important role in the ANE values.
A ferroelectric crystal with charge-free surface conditions contains polarized domains which can form a flux closure with zero net polarization. In the presence of an external electric field, the flux closure in a two-dimensional continuum reorients its spontaneous polarization to align with the field. Based on this concept of ferroelectric switching coupled with mechanical straining, we demonstrate the working principle of a ferroelectric nano-actuator. The behavior of the actuator is explored under the action of electro-mechanical loading and its mechanism is simulated with a 2D phase-field model. The design of nano-actuator is modified to achieve greater actuation displacements by bending a thin device.
Currently, large efforts are going on to scale up PZT thin film processes for large volume MEMS fabrication. It is critical to complete the scaling up with optimized film properties. In this work we report about microstructural control and piezoelectric properties of RF magnetron sputtered PZT (Pb(Zrx,Ti1−x)O3) thin films. The former is a prerequisite to achieve good properties homogeneously on the entire wafer, and with a good repeatability. We focus on the use of a commercial tool capable to reach a deposition rate of 1nm/sec with a thickness uniformity better than +/-3%. We show particularly how the texture can be chosen between (100) and (111) orientation upon tuning the thickness of a very thin TiO2 seed layer on fully passivated Pt electrodes. The surface morphology as resulting from the various grain shapes is strongly influenced by the self-bias established on the substrate, and by the growth temperature. PZT films with compact grain structure and flat surface reached a transverse piezoelectric coefficient e31,f of -23±1 C/m2 in the actuator mode (converse piezoelectric effect) and a dielectric strength of 0.5MV/cm. Both are remarkable values for un-doped, pure PZT thin films.
We examine the electron transport that occurs within a zinc-oxide-based two-dimensional electron gas using Monte Carlo simulations. The sensitivity of the results to variations in the lowest energy conduction band valley electron effective mass is examined. Increased values of the electron effective mass result in diminished electron drift velocities and reduced sensitivity to the free electron concentration. In agreement with our previous studies for a fixed value of the electron effective mass , we find that the reduced scattering due to the screening of the impurity and polar optical scattering leads to a slightly higher mobility of the 2DEG at low-fields but reduces the peak velocity, since gaining a higher energy due to the reduced polar optical phonon scattering enhances the effects of the non-parabolicity within this material.
Silver nanoparticle (AgNP) is one of the elegant material because its uses in various fields. In this study, AgNPs have been prepared by using Peltophorum pterocarpum (PP) flower extract as reducing and capping agent and aqueous silver nitrate (aq.AgNO3) as silver precursor. The synthesized nanoparticles were characterized using Ultra Violet - Visible (UV-Vis) spectroscopy, High Resolution Transmission Electron Microscope (HR-TEM) and Fourier Transform Infrared Spectroscopy (FT-IR), which reveals the formation of nanosized particles. The UV-Vis spectrum shows an absorption peak around 430nm. HR-TEM images of AgNPs with clear morphology and well dispersed prepared AgNPs.
In this paper, the authors have reported the structural and photoluminescence (PL) studies of pure and nickel (Ni) doped zinc oxide (ZnO) nanoparticles synthesized by the solution combustion method. The structural, morphological and optical studies are carried out by powder x-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM) and PL spectra, respectively. The XRD pattern indicates that the prepared particles are in hexagonal wurtzite structure with the average crystalline size is around 35-50nm. Room temperature PL shows the near band edge related emission and the results are related several intrinsic defects in the ZnO nanoparticles.
In this paper, the effect of shock compression on the synthesis of a Bi-based oxide superconductor was investigated. Bi1.85-Pb0.35-Sr1.90-Ca2.05-Cu3.05-Ox calcined powder was shock-compacted around 20 GPa and 30 GPa, and divided specimens were annealed at 845 °C for 1, 6 and 48 hours. The specimens were evaluated by x-ray diffraction and scanning electron microscope.
ZnO nanorods were grown up from as-deposited ZnO film on which the zinc self-catalysts generated by a novel reducing method. Well aligned ZnO nanorods with a uniform high aspect ratio were grown up on multi-annealed samples. The length of nanorods depended significantly on the reaction time in the hydrothermal synthesis.
Graphite and pregraphitic carbons capable of reversibly reacting with lithium ions are hosts commonly used in Li-ion cells. As a continuation of previous work, we have used chemical vapour deposition of benzene and silicon-containing precursors to prepare carbons containing nanodispersed silicon. The silicon resides within the unorganized regions in the pregraphitic carbons. These materials reversibly react with lithium in electrochemical cells and the reversible specific capacity has been known to increase from -300 mAhg−1, in the absence of silicon, to near 500 mAhg−1 as silicon is added. We also report on Si-O-C materials which have been shown to reversibly react with Li in electrochemical cells with reversible specific capacities as high as 770mAhg−1. These materials have been made by thermal pyrolysis of siloxane polymers and epoxy-silane composites prepared from hardened mixtures of epoxy novolac resin and epoxy-functional silane. These materials all show promise for use as anode materials in advanced rechargeable lithium batteries.
This paper presents a phase-zero evaluation case of installing on-off-board hybrid powered Electric Motor Vehicle (EMV) in existing and new local line and reports development of a model fuel cell powered locomotive. EMV such as electric car and locomotive are a new conceptual EMV using hybrid power between off-board substation and on-board Regenerative Fuel Cell (RFC) power system with Metal Hydride (MH) stored hydrogen generated with water electrolyzer by off-board surplus power. In this study, it is estimated a possibility to close power gap over 30 % in placing the new conceptual vehicle. The Locomotive is a 110 cm long locomotive powered by a 20 W PEMFC configured with 20 cells and supplied with about 2 g hydrogen, from a cylinder of 100 g metal hydride, and natural convection air (02). Measuring 50 cm (W), 50 cm (H), and weighting 25.9 kgf, the locomotive has a permanent magnet motor with a rated power 38 W (12 V, 3 A) and ran on railway that has a gauge of 126 mm (3'6“/8.5=4.94”), a length of 100 m. The performance of this train was acceleration of 0.5 m/s, cruising speed of 4.1 m/s at traction force of 15.8 N (1.6 kgf), average rolling friction of 5 N (460 gf).
The crystal structures of the undischarged, heat-treated electrolytic manganese dioxide (HEMD) and discharge products are characterized by high spatial resolution convergent beam electron diffraction (CBED). The results are compared with the x-ray diffraction (XRD) patterns characterized by broad, diffuse peaks. The CBED results for HEMD show that the starting cathodic material has the pyrolusite space group, but with a range of c/a ratios. The variability of the lattice parameter from grain to grain is found to coincide with the broadening on the low angle side of the XRD peaks. The CBED patterns of discharge products suggest a reduction range in c/a ratios and the formation of another phase.
Aluminum is of interest as a constituent for Li battery electrodes due to its low cost and low mass, and because ab initio calculations indicate that solid solution of LiAlO2 with LiMO2 (M = transition metal) in the α-NaFeO2 structure can increase intercalation voltage . In this study, we investigated the effect of Al doping on LiCoO2 and LiMnO2. Single phase LiAlyCo1-yO2 has been synthesized up to y = 0.5 by firing homogenous hydroxide precursors. A systematic increase in the open circuit voltage is observed with Al content. In LiAlyMn1-yO2, the addition of LiAlO2 stabilizes LiMnO2 in the α-NaFeO2 structure under conditions where neither endmember is stable in the structure. High reversible capacity was obtained over both a 4 V and 3 V plateau, indicating that the compound transforms to a spinel-related structure during cycling, but that the cooperative Jahn-Teller distortion is suppressed.
Electric double-layer capacitors based on charge storage at the interface between a high surface area activated carbon electrode and a propylene carbonate solution are widely used as maintenance-free power sources for IC memories and microcomputers. New applications for electric double-layer capacitors have been proposed in recent years. The popularity of these devices is derived from their high energy density compared with conventional capacitors and their long cycle life and high power density relative to batteries.
The performance of the capacitor depends not only on the materials used in the cells but also on the construction of the cells. The performance of power capacitors for large power sources as well as materials and construction of these capacitors are described.
Li1+xV3O8 (LT-M form) was obtained by sol-gel method in CH3OH. This form, prepared at 350°C, possessed smaller grain size and better electrochemical performance than the HT form prepared by conventional high temperature synthesis. High discharge capacity (372 mAh·g−1: x = 4.0) and reversible discharge and charge cycle were attained. When heated at 200°C, CH3OH molecules remained in the compound and crystallinity became lower by lithium insertion over x = 2.0. The lithium de-intercalation was irreversible.
It is important for the commercialization of molten carbonate fuel cell (MCFC) to improve the endurance and the reliability of the electrolyte plate. The electrolyte-loss in the electrolyte plate increases the cell resistance and deteriorates the cell voltage. The formation of cracks in the electrolyte plate causes a gas cross leakage between the fuel gas and the oxidizer gas. The pore structure of electrolyte plate must be stable and fine to support liquid electrolyte under MCFC operation. It is necessary to prevent the formation of cracks in electrolyte plate during thermal cycling. We have improved the stability of electrolyte plate using advanced LiAIO2 powder and improved the durability of electrolyte plate for thermal cycling by the addition of the ceramic fiber.
The initial cell voltage using electrolyte plate with advanced LiAIO2 powder was 820mV at current density 150mA/cm2 and the decay rate of cell voltage was under 0.5%/1000h for 8,800h. According to the post analyses, the pore structure of the electrolyte plate did not change. The stability of advanced LiAIO2 powder was confirmed. It was proved that the electrolyte plate reinforced with ceramic fiber is effective for thermal cycling.
The oxygen permeation through an oxide membrane with bulk composition SrFeCo0.5O3.25-δ has been measured as a function of both oxygen partial pressure and temperature. The results of the pressure dependence of the permeation indicate that the oxygen transport in this membrane is dependent primarily on the bulk diffusion rate. Although the permeation experiments were carried out at temperatures within, or very close to, the range where SrFeCo0.5O3.25-δ is stable as a pure single phase, the membrane was found to consist of SrFe1.5-xO3.25-δ(x = ∼0.42) together with fractions of Sr(Co,Fe)O3-δ perovskite and Co-Fe oxide that formed as stable phases during densification of the membrane at high temperature (1090°C). These additional phases persisted in the membrane during the permeation measurements.