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The efficacy of the unified protocol of the transdiagnostic treatment for emotional disorders (UP) has been poorly studied in patients with depressive disorders. This study aimed to examine the efficacy of UP for improving depressive symptoms in patients with depressive and/or anxiety-related disorders.
This assessor-blinded, randomized, 20-week, parallel-group, superiority study compared the efficacy of the UP with treatment-as-usual (UP-TAU) v. wait-list with treatment-as-usual (WL-TAU). Patients diagnosed with depressive and/or anxiety disorders and with depressive symptoms participated. The primary outcome was depressive symptoms assessed by GRID-Hamilton depression rating scale (GRID-HAMD) at 21 weeks. The secondary outcomes included assessor-rated anxiety symptoms, severity and improvement of clinical global impression, responder and remission status, and loss of principal diagnosis.
In total, 104 patients participated and were subjected to intention-to-treat analysis [mean age = 37.4, s.d. = 11.5, 63 female (61%), 54 (51.9%) with a principal diagnosis of depressive disorders]. The mean GRID-HAMD scores in the UP-TAU and WL-TAU groups were 16.15 (s.d. = 4.90) and 17.06 (s.d. = 6.46) at baseline and 12.14 (s.d. = 5.47) and 17.34 (s.d. = 5.78) at 21 weeks, with a significant adjusted mean change difference of −3.99 (95% CI −6.10 to −1.87). Patients in the UP-TAU group showed significant superiority in anxiety and clinical global impressions. The improvement in the UP-TAU group was maintained in all outcomes at 43 weeks. No serious adverse events were observed in the UP-TAU group.
The UP is an effective approach for patients with depressive and/or anxiety disorders.
The magnesium compound Mg2Si and its solid solutions are expected as n-type thermoelectric (TE) material because they are non-toxic, have a large Clarke number, and are light weight. In this study, we improved TE performance by doping Ge into Sb-doped Mg2Si to cause phonon scattering and increase carrier concentration. A bulk of Sb-doped Si-Ge alloy as the raw material was fabricated using an arc-melting method. A high-purity Mg2Si was synthesized from metal Mg and Sb-doped Si-Ge alloy using spark plasma sintering equipment. For the samples with the same Sb concentration, the electrical conductivity was equivalent. On the other hand, the Seebeck coefficient was dependent on Ge concentration. Due to phonon scattering, thermal conductivity decreased by a small amount of Ge doping and κph dominated for thermal conduction. The minimum thermal conductivity of Mg2Si0.90Ge0.10 was 2.25 W/mK (κph: 2.06 W/mK, κel: 0.19 W/mK). The dimensionless figure of merit (ZT) for the Mg2Si0.945Ge0.05Sb0.005 sample was higher than that of the others due to reducing thermal conductivity and increasing carrier concentration. The maximum ZT was 0.47 at 713 K.
We established a Ca1-xBixMn1-yNiyO3 (0 ≤ x, y ≤ 0.1) powder library using a combinatorial system based on the electrostatic spray deposition method. Single phase perovskite-type structures were identified in all of the powders. To measure electrical conductivity, the powder library was subjected to high-pressure (200 MPa) and heat-treated at 950°C for 1 hour in an oxygen atmosphere. As a representative example, the electrical conductivity of 5%-Bi-substituted CaMnO3-δ showed a higher value (63 S·cm-1) than an unsubstituted powder (13 S·cm-1). The improved electrical conductivity, on the other hand, was still very far from the ideal result (167 S·cm-1).
In this study, we fabricated Mg2Si from metal Mg and Si with different particle sizes (425 - 300, 300 - 180, and 75 μm or less) using spark plasma sintering (SPS) equipment. Additionally, the Mg2Si formation was investigated. A sieved Si powder was mixed with metal Mg powder in an inert gas (Ar) atmosphere. The mixture was placed in a graphite die while still in an Ar atmosphere and subjected to SPS at 923 K and 1113 K. The obtained sintering bodies were Mg2Si particles with a size of about 5 μm. Then, the sintered bodies were evaluated by X-ray diffraction (XRD). As a result, it was confirmed that generation of Mg2Si increased with decreasing Si particle size.
Magnesium silicide (Mg2Si) has attracted much interest as an n-type thermoelectric material because it is eco-friendly, non-toxic, light, and relatively abundant compared with other thermoelectric materials. In this study, we tried to improve the thermoelectric performance by doping Sb and Ge in the Mg2Si, as well as further optimizing x in the carrier concentration to cause phonon scattering. A high purity Mg2Si was synthesized from metal Mg and Sb doped Si-Ge alloy by using spark plasma sintering (SPS) equipment. The sintered samples were cut and polished. They were evaluated by using X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses. The carrier concentration of the samples was measured by using Hall measurement equipment. The electrical conductivity and Seebeck coefficient were measured by using a standard four-probe method in a He atmosphere. The thermal conductivity was measured by using a laser-flash system. We succeeded in obtaining a Sb doped Mg2Si0.95Ge0.05 sintered body easily without any impurities with the SPS equipment. The electrical conductivity of the sample was increased, and thermal conductivity was decreased by increasing the amount of doped Sb. The dimensionless figure of merit ZT became 0.74 at 733 K in the Mg2Si0.95-xGe0.05Sbx sample with x = 0.0022.
NaxCoO2 has a particularly high contact resistance because it forms an insulated layer of NaHCO3 and Na2CO3, which are produced in a chemical reaction with carbon dioxide and water in air on the surface. In this study, we tried to improve the interface resistance between NaxCoO2 and Ag sheet electrodes by connecting these materials with the spark plasma sintering (SPS) technique. The interface resistance between NaxCoO2 and Ag sheet electrodes connected by SPS is compared with that connected with Ag paste. In an experiment, the interface resistance of a sample treated by decrease to less than 1/600 of the former value. It is thought that the NaHCO3 and Na2CO3 insulated layer is decomposed through the application of a large value of applied DC current by using the SPS technique.
It is well known that tungsten tri-oxide (WO3) exhibits electrochromic and gasochromic properties. When Pt-nanoparticle-dispersed tungsten oxide (Pt-WO3) is exposed to hydrogen gas, the optical and electrical properties of the Pt-WO3 change drastically. Consequently, it is expected that thin films of WO3 can be applied as hydrogen gas leakage sensors. In this study, thin films of Pt-WO3 were prepared on glass substrates using a sol-gel process. The optical and electrical properties of the films were evaluated. Amorphous and crystalline WO3 were easily obtained by changing the heat-treatment temperature. The ion diffusion coefficient of the film depended on the WO3 structure (i.e., whether it was amorphous or crystalline) because the density of amorphous WO3 is lower than that of crystalline WO3. Films with low crystallinity were found to have superior chromic properties to both those with high crystallinity and amorphous films. Thin films of Pt-WO3 prepared at 673K showed the largest change in optical transmittance and electrical conductivity when exposed to H2 gas compared with thin films prepared at other temperatures. When this film was exposed to 100% H2 gas, the normalized transmittance decreased rapidly (in less than 0.2 sec) from 100% to almost 50%. The optical absorbance of the film was dependent on the H2 gas concentration (mixed with N2 gas) in the range from 0.1 to 5% and the relationship between them was linear. The relationship between the electrical conductivity and hydrogen gas concentration (mixed with N2 gas) in the range from 100 to 10000ppm was also linear.
Field electron emission model of hydrogen-terminated n-type diamond was discussed. Ultra-violet photoelectron spectroscopy characterizations indicated that the electron affinity was -0.7 eV and an internal barrier of about 3.5 eV existed on the surface. Field electron emission properties depended on anode-diamond distances. Schottky barrier lowering model suggested that this internal barrier was lowered by the electric field (5.4x106 V/cm) applied onto the negative electron affinity surface of the H-terminated n-type diamond.
The overnight preservation of bovine ovaries would be highly useful in the subsequent harvest of viable oocytes for reproductive study. The present study aimed to optimize conditions for overnight preservation of bovine ovaries by examining the effects of temperature, solution and supplementation. In Experiment 1, the rate of development to the blastocyst stage of oocytes derived from ovaries preserved at 15°C was higher than that at either 5 or 25°C (p < 0.05). In Experiment 2, the rate of development to the blastocyst stage of oocytes derived from ovaries preserved in University of Wisconsin solution was higher than when PBS or saline was used (p < 0.05). In Experiment 3, oocytes preserved in saline supplemented with 0.3 mM glutathione (GSH) exhibited an increase in the rate of blastocyst formation compared with oocytes supplemented with 0 or 3 mM GSH (p < 0.05). In Experiment 4, supplementation with 10 μM epigallocatechin gallate during ovary preservation increased the rate of blastocyst formation (p < 0.05). The blastocysts derived from ovaries stored in saline supplemented with GSH at 15°C for 24 h were shown to develop into normal offsprings following transfer to recipient heifers. Our studies indicate that bovine IVM/IVF embryos derived from ovaries preserved in saline supplemented with an antioxidant at 15°C for 24 h can successfully develop to the blastocyst stage and result in offspring.
Interface states produced at the interface between an insulator and GaN semiconductor determine the performance of GaN metal-insulator-semiconductor (MIS) field effect transistors. Therefore, it is important to know details of interface states characteristics to improve device performances. For above purpose, we have fabricated GaN MIS capacitors, then carried out capacitance-voltage (CV) and deep level transient spectroscopy (DLTS) measurements, and analyzed the obtained results in detail.Wafers used in this study were n-type GaN grown on sapphire substrates by metal organic chemical vapor deposition. A film of SiN was deposited as an insulating layer using electron-cyclotron-resonance plasma-assisted deposition at room temperature, then samples were annealed at 400, 600 or 800°C in N2 atmosphere for 10 min.CV measurements were performed for all the samples at various frequencies and bias sweep rates in the dark condition. CV curves of all the samples exhibited ledges in the curves. Here, ledge indicates a region of which capacitance is independent of applied bias. Although each sample was annealed at each different temperature, it was observed at the same surface potential for all the samples. This result indicates that the Fermi level of the GaN/SiN interface is pinned by a particular trap. In addition, the shape of the CV curve depended on both frequency and bias sweep rate, and it was not observed in the results obtained by a quasi-static capacitance voltage measurement. This can be explained that the shape of ledge is determined by the quasi-equilibrium between a filling rate of traps and a bias sweep rate or test frequency.
In the positive bias region of the ledge, a hysteresis window of the CV curve had some dependence on frequency but little dependence on bias sweep rate. On the other hand, in the negative bias region of the ledge, it had little dependence on frequency but obvious dependence on bias sweep rate. These dependences indicate two different traps and related to the ledge formation. The trap energy level related to the sweep rate dependence is estimated to be 0.34 eV by the temperature dependence of the width of hysteresis window.
Deep level transient spectroscopy measurements were carried out to characterize the trap levels observed in the CV curves. Trap levels with activation energies of 0.32 and 0.78 eV were observed . The former is almost equal to 0.34 eV obtained from the temperature dependence of the width of hysteresis window. The latter is similar to the interface trap reported by Nakano et al., which is considered to be originated from the complexes of Si and surface defect . E. Shibata et al., Ext. Abstracts 2008 IMFEDK, Osaka, pp.69-70. (2008). Y. Nakano and T. Jimbo, Appl. Phys. Lett. 80, 4756 (2002).
In this paper, we measured the field emission properties of reconstructed P-doped diamond under various anode-diamond distances and compared with the oxidized surface. Voltage drops in the vacuum was estimated to be 4.95 and 26.6 V/μm for the reconstructed and the oxidized, respectively. Moreover, we calculated the barrier height ratio between each surface. Our data indicates the changes in electron affinity strongly affect on the field emission properties.
Electric field of less than 5 V/um is enough to extract electrons from CVD diamond, whereas field of one to two orders of magnitude higher is needed to extract electrons from metal emitter tips. Diamond has various advantages as an electron emitter in addition to the low-threshold voltage, negative electron affinity (NEA), high thermal conductivity, and high chemical stability. The difficulty in clarification of electron emission mechanism is the factor preventing diamond from being used in practical Quite a few numbers of possible mechanisms have been proposed based on conventional emission current-anode voltage (I-V) characteristics, however, difficulty remained in the determination of origin for emitting electrons. In our previous study, we have succeeded in determining the origin for lightly nitrogen (N)-doped CVD diamond by using combined x-ray photoemission spectroscopy / ultraviolet photoemission spectroscopy / field emission spectroscopy (XPS/UPS/FES) system. The origin at 1.47 eV above valence band maximum (VBM) was consistent with donor level for aggregated N. The origin was at VBM for natural IIb diamond measured as a reference, indicating the emitted electrons strongly depend on the dopant In this study, the origin of emitting electrons for heavily N-doped CVD diamond was characterized by the means of combined XPS/UPS/FES. Extremely low-threshold electron emission at 0.5 V/um is still one of the lowest threshold voltages. Such a low-threshold emission may be possible if electrons are somehow injected to conduction band of diamond and emitted into vacuum through NEA surface. Hence, we strongly believe the determination of the origin for heavily N-doped CVD diamond leads to the clarification of mechanism for low-threshold electron emission from diamond. The system in which we have developed for this study consists of ultraviolet source built in an X-ray photoelectron spectrometer. The diamond sample could be negatively biased up to 4kV relative to the mesh grid for FES. Individual spectroscopy of XPS was performed prior to the combined spectroscopy to determine any possible contaminants on CVD diamond. Peaks referred to C1s and O1s of diamond were observed in addition to Gold, used in a mesh grid set above the sample. Combined spectroscopy of UPS/FES was then, conducted on the CVD diamond to identify the origin of field emitted electrons. The diamond was first illuminated by He I excitation for photoemission. NEA with the typical spectra shape for diamond was observed. After confirming stable operation of individual UPS, negative voltage was applied simultaneously for field emission. Exceeding threshold voltage, a sharp peak, which can be referred to field-emitted electrons appeared in addition to typical UPS spectra. The origin of emitting electrons as well as its dependence on the applied voltage will be discussed.
Electric field of less than 5 V/μm is enough to extract electrons from diamond, whereas field of one to two orders of magnitude higher is needed to extract electrons from metal emitter tips. Despite such low-threshold field, the difficulty in clarification of electron emission mechanism is the factor preventing diamond from being used in a practical use. Quite a few numbers of possible mechanisms were proposed to better understand the origin and properties of the observed emission. Most of these mechanisms were, however, based on the conventional I (Emission current)-V (Anode voltage) characteristics. Energy distribution of the field-emitted electrons is essential in direct clarification of the mechanism. In this study, combined XPS/UPS/FES system was used to characterize the electron emission mechanism of doped chemical vapor deposited (CVD) diamond. The results indicated successful observation of the origin of field-emitted electrons from doped CVD diamond comparison with natural diamond, used as a reference.
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