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To investigate whether the depressive tendency of adolescents are associated with certain personality traits in a stratified sample in eastern Taiwan.
Students who were sampled from 6 junior high and 25 primary schools in a multi-stratified manner were invited to join the study and asked to complete the Center for Epidemiologic Studies Depression Scale (CES-D) and the Junior Eysenck Personality Questionnaire (JEPQ) administrated together with other measurements of behavioral problems and life events. Effects of gender and grades on the score of the CES-D and the JEPQ and all its four subscales (N, E, P, and L) were analyzed. Correlation between the CES-D and the JEPQ's subscales were explored.
Data from 3222 participants was analysed. Scores of CES-D and all four subscales (N, E, P, and L) of JEPQ were not influenced by gender. Scores of CES-D of participants from junior high school (grade 7-9) were significantly higher than those from primary schools (grade 4-6) but not similar finding in JEPQ scores. Gender difference was not noted in the low depressive tendency group, but there's more girls (59.2%) than boys (41.8%) in the high depressive group. Participants in the high depressive tendency group had significantly higher scores of N and P subscale, but not E subscale of JEPQ than those in the low depressive tendency group.
Different aspects of personality might be correlated differently to the tendency of depression among adolescents. Whether there's developmental causation warrants further analyses and explorations.
The aims of this study were to examine whether different domains of quality of life (QOL) are differently affected by depressive disorders by comparing QOL of subjects with and without depressive disorders, and to examine the association of QOL with self-stigma, insight and adverse effects of medication among subjects with depressive disorders.
The QOL on the four domains of the WHOQOL-BREF Taiwan version were compared between the 229 subjects with depressive disorders and 106 control subjects without depressive disorder. Among the subjects in the depressive group, the association between the four QOL domains and subjects' self-stigma, insight, and adverse effects of medication were examined using multiple regression analyses by controlling for the influence of depression, socio-demographic and clinical characteristics and family function.
The results found that subjects with depressive disorders had poorer QOL on the physical, psychological and social relationship domains than the non-depressive control group. The depressive subjects who had more severe self-stigma had poorer QOL on all four domains. The depressive subjects who had higher levels of awareness of illness had poorer QOL on the physical and psychological domains. The depressive subjects who perceived more severe adverse effects from medication had poorer QOL on the physical, psychological and environmental domains.
The results of this study demonstrate that different domains of QOL are differently affected by depressive disorders, and that clinicians must consider the negative influences of self-stigma, insight and adverse effects from medication on QOL of subjects with depressive disorders.
Coaxial relativistic backward wave oscillator with the rippled inner conductor not only increases the output efficiency but also results in the serious phenomenon of pulse shortening in experiments. Our research indicates that the two main mechanisms leading to the pulse shortening are the electron beam interruption and combining effects of the explosive field electron emission and the secondary electron multipactor on the surface of the slow-wave structure. In order to enhance its power capacity the electrodynamic structure is modified by detailed analysis of the field distribution in the coaxial slow-wave structure. The appropriate resonant reflector and the electron collector are developed for the application of the coaxial relativistic backward wave oscillator. A series of surface treatment is applied to enhance the power capacity of the coaxial RBWO. In the experiment, the microwave pulse duration is increased from less than 10 ns to 20 ns, and the output efficiency is enhanced from less than 20% to 34% employing the electron beam pulse of the full width at half maximum 28 ns. The peak power of 1.01 GW at the frequency of 7.4 GHz is achieved. It is found that the output efficiency of the coaxial RBWO is likely to be advanced if its power capacity can be boosted further.
Chemical wet etching on c-plane sapphire wafers by three etching solutions (H3PO4, H2SO4, and H3PO4/H2SO4 mixing solution) was studied. Among these etching agents, the mixing H3PO4/H2SO4 solution has the fastest etching rate (1.5 μm/min). Interestingly, we found that H2SO4 does not etch the c-plane sapphire wafer in thickness; instead, a facet pyramidal pattern is formed on the c-plane sapphire wafer. GaN light-emitting diode (LED) epitaxial structure was grown on the sapphire wafer with the pyramidal pattern and the standard flat sapphire wafer. X-ray diffraction and photoluminescence measurement show that the pyramidal pattern on the sapphire wafer improved crystalline quality but augmented the compressive stress level in the GaN LED epilayer. The horizontal LED chips fabricated on the pyramidal-patterned sapphire wafer have a larger light output than the horizontal LED chips fabricated on the standard flat sapphire wafer by 20%.
Efficient generation regime with a high power output has been experimentally realized in a klystron-like relativistic backward wave oscillator, in which a modulation cavity is inserted between the slow wave structure to decrease the energy spread of modulated beam electrons, and an extraction cavity is employed at the end of the slow wave structure to further recover energy from the electron beam. At a guiding magnetic field of 2.2 T, a microwave pulse with power of 6.5 GW, frequency of 4.26 GHz, pulse duration of 38 ns, and efficiency of 36% was generated when the diode voltage was 1.1 MV, and diode current was 16.4 kA. When the diode voltage was 820 kV, efficiency up to 47% with microwave power 4.4 GW was also realized experimentally.
A novel hard transmission X-ray microscope (TXM) at the Stanford Synchrotron Radiation Lightsource operating from 5 to 15 keV X-ray energy with 14 to 30 μm2 field of view has been used for high-resolution (30–40 nm) imaging and density quantification of mineralized tissue. TXM is uniquely suited for imaging of internal cellular structures and networks in mammalian mineralized tissues using relatively thick (50 μm), untreated samples that preserve tissue micro- and nanostructure. To test this method we performed Zernike phase contrast and absorption contrast imaging of mouse cancellous bone prepared under different conditions of in vivo loading, fixation, and contrast agents. In addition, the three-dimensional structure was examined using tomography. Individual osteocytic lacunae were observed embedded within trabeculae in cancellous bone. Extensive canalicular networks were evident and included processes with diameters near the 30–40 nm instrument resolution that have not been reported previously. Trabecular density was quantified relative to rod-like crystalline apatite, and rod-like trabecular struts were found to have 51–54% of pure crystal density and plate-like areas had 44–53% of crystal density. The nanometer resolution of TXM enables future studies for visualization and quantification of ultrastructural changes in bone tissue resulting from osteoporosis, dental disease, and other pathologies.
The field distribution and the restraint effect of multipactor and plasma discharge on the periodic triangular surface have been theoretically and experimentally analyzed. It has been found by computational and simulative analysis that the periodic profile can quickly restrain or weaken multipactor and plasma discharge in low pressure within several microwave periods. Considering the field enhancement, increasing the slope angle, advancing the electric field, and lowering the frequency can enhance the multipactor suppression. X-band giga-watt high power microwave experiment with 20 ns short pulse was conducted. It was demonstrated that the periodic profile can effectively improve the breakdown threshold and slower the speed of tail erosion.
A vircator with a coaxial cavity has the potential to increase the beam–microwave conversion efficiency. According to the E-field distribution pattern of the modes in the anode cavity of a coaxial vircator, the resonant frequency band of the injected electron beam and the lowest two operating modes are derived. The main frequency of the virtual cathode is also deduced. The optimal operating frequency and high-efficiency designing method of a coaxial cavity vircator is discussed. An experimental setup is designed and built to test the high-power microwave (HPM) generation mechanism described by theoretical analysis as well as increase the power efficiency. HPM frequency obtained in the experiment is in good agreement with the analysis. The power and energy efficiencies obtained in the experiment are, respectively, 8.7% and 6.8% with 50 ns pulse width. Frequency and phase stable HPM radiation is observed as well as pulse shortening is evidently depressed.
The Sm-based Sm–Al–Ni glass-forming system was investigated using our e/a- and cluster-related criteria. Three bulk metallic glasses (BMGs) Sm54Al23Ni23, Sm56Al22Ni22, and Sm58Al21Ni21 were obtained by suction casting into rods with a diameter of 3 mm. All of them shared a constant e/a = 1.5 and fell along the e/a-constant composition line in the ternary composition chart. The Sm54Al23Ni23 BMG exhibiting the largest Trg was located at the intersection point of the e/a-constant line and the Sm7Ni3-Al cluster line, with thermodynamic parameters of Tg = 548 K at a heating rate of 20 K/min, Tg/Tm = 0.634, and Tg/Tl = 0.615. The Sm7Ni3 cluster was a capped trigonal prism derived from the SmNi phase.
The strain status of the buried InAs self-assembled quantum dot was comprehended by measurement first time. Results show the in-plane strain is compressive and lattice in the growth direction is lager than the lattice of GaAs. The strain of the sample annealed at 650 degree relaxes in the growth direction. The growth and the lateral direction become relaxed in the sample annealed at 750 degree.
Sol-gel derived catalyst systems of cobalt, nickel, and iron were used in the growth of gallium nitride (GaN) nanowires by thermal chemical vapor deposition. A diffusion barrier matrix of titania (TiO2) has been used in which the catalysts were dispersed to have control of the catalyst particle sizes and hence on the size and morphology of the GaN nanowires. This single-step and cost-effective processing of the catalyst bed produced good-quality GaN naowires with comparable structural and optical properties with those previously reported. In a particular case, a stress-induced cubic admixture to the otherwise hexagonal structural symmetry was observed. The samples were characterized by high-resolution scanning electron microscopy, x-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and cathodo-luminescence studies.
The electromigration behavior of the composite solder composed of eutectic and high-lead SnPb was investigated with 5.7 × 104 A/cm2 current stressing. Voids and hillocks were found only within the eutectic solder, and the high-lead solder remained intact. Electromigration was accelerated dramatically at 150 °C, and Pb became the major migration species of eutectic SnPb for the microstructure change at the anode. The polarity of the opposite current direction was also studied. When electrons drift from the eutectic side to the high-lead side, voids occurred at the eutectic–Cu interface whereas hillocks accumulated at the eutectic–high-lead interface. When the current was reversed, voids occurred at the eutectic–high-lead interface whereas hillocks accumulated at the eutectic–Cu interface. The anchoring effect, which results from the attaching of the lead-rich grains in the eutectic solder to the high-lead solder, was considered to retard the electromigration damage only in this current direction.
The structural evolution in amorphous silicon and germanium
thin films has been investigated by high-resolution transmission
electron microscopy (HRTEM) in conjunction with autocorrelation
function (ACF) analysis. The results established that the structure
of as-deposited semiconductor films is of a high density of
nanocrystallites embedded in the amorphous matrix. In addition,
from ACF analysis, the structure of a-Ge is more ordered than
that of a-Si. The density of embedded nanocrystallites in amorphous
films was found to diminish with annealing temperature first,
then to increase. The conclusions also corroborate well with
the results of diminished medium-range order in annealed amorphous
films determined previously by a variable coherence microscopy
The self-constructed Super-Light telescope of the National Central University is now ready for open use. Systematic studies of RR Lyraes stars and other variables are outlined and some preliminary results are introduced.
γ-hydride precipitation and growth in a zirconium bi-crystal were simulated using a phase field kinetic model. The temporal evolution of the spatially dependent field variables is determined by numerically solving the time-dependent Ginzburg-Landau equations for the structural variables and the Cahn-Hilliard diffusion equation for the concentration variable. The morphology evolution of γ-hydride with and without external load was simulated. It is demonstrated that nucleation density of the hydride at the grain boundary increases as compared to the bulk and favorable hydride precipitation at the grain boundary become weaker when an external load is applied.
Transmission electron diffraction patterns from ultra-thin aromatic and aliphatic organic films at beam energies of 200 eV–1 keV have been recorded in a custom low energy electron transmission (LEET) chamber. A significant reduction of the molecular damage cross-section, measured by fading of diffraction spots, was found for thin films of the aromatic perylene when the beam energy was reduced from 400 to 200 eV. The corresponding measurements for the aliphatic tetracontane showed a smaller “threshold energy” and the differences are discussed. Electron beam damage from other aromatic materials has also been studied at low energy. Comparison of the carbon K shell ionization cross-section and the measured damage cross-sections show that carbon K-shell ionization is strongly correlated with the damage observed in aromatics at beam energies higher than 284 eV. Calculation of the minimum number of unit cells needed for imaging a single molecule, and comparison of calculated elastic with measured damage cross-sections both indicate new possibilities for imaging biomolecules with low energy electrons.
We demonstrate a self-organized pattern formation on vicinal Si(111) surfaces that are miscut toward the  direction. All the patterns, consisting of a periodic array of alternating (7×7) reconstructed terraces and step-bunched facets, have the same periodicity and facet structure, independent of the miscut angle; while the width of the facets increases linearly with miscut angle. We attribute such unique pattern formation to a surface faceting transition that involves two transition steps: the first step forms a stress-domain structure defining the universal periodicity; the second step forms the low-energy facets controlling the facet width.
This communication reports on the microstructure and interdiffusion observed in a new NbSn2/Nb metallization structure on SiO2, previously reported [H. S. Chen et al., Appl. Phys. Lett. 66, 2191 (1995)]. The as-deposited NbSn2 layer was found to be amorphous. After heating, the NbSn2 becomes polycrystalline and heavily diffused with Au from the Au-Sn solder. The Nb layer remains pure and intact after heating. The microstructure, compositions, and phases of the Au-Sn solder layer are also presented.