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941.
942.
Zhang C. P. Hao T. L. Chen P. Liang J. Wang C. Z. Kang H. X. Gao R. L. Fu X. B. 《Laser Physics》2011,21(12):2122-2127
The aim of this paper is to study the effect of low-level laser irradiation (LLLI) on proliferation of myoblasts in culture.
Myoblasts derived from rat skeletal muscle were irradiated by He-Ne laser with different doses. Compared with nonirradiated
control group, the number of myoblasts increased when the cells in normal culture conditions were exposed to the laser of
specific energy density. The amount of cells with proliferating cell nuclear antigen (PCNA) positive expression and the 5-bromo-2′-deoxyuridine
(BrdU) incorporation rate after laser irradiation were also higher than that of the control group, suggesting that LLLL at
certain doses can effectively enhance myoblasts growth activity in vitro. This study firstly demonstrated that stimulating
myoblasts to enter into proliferative stage from initial resting state was an important mechanism of regeneration and repair
of injured skeletal muscle promoted by LLLI in clinical treatment. 相似文献
943.
We report a continuous-wave (CW) coherent green radiation at 532 nm by intracavity frequency doubling generation of 1064 nm
Nd:Gd0.18Y0.82VO4 laser. With incident pump power of 18.2 W, output power of 1.08 W at 532 nm has been obtained using a 5 mm-long KTP crystal.
The optical conversion efficiency was up to 5.9%. At the output power level of 1.08 W, the output stability is better than
5%. The beam quality M2 values were equal to 1.26 and 1.12 in X and Y directions, respectively. 相似文献
944.
Diode-pumped Pr<Superscript>3+</Superscript>:YAlO<Subscript>3</Subscript>/LBO violet laser at 374 nm
We report a diode-pumped Pr3+:YAlO3 laser emitting at 747 nm. A power of 232 mW at 747 nm has been achieved in continuous-wave operation with a diode emitting
2 W at 448 nm. Furthermore, intracavity second-harmonic generation in continuous-wave mode has also been demonstrated with
a power of 52 mW at 374 nm by using a LBO nonlinear crystal. The fluctuation of the violet output power was better than 2.3%.
The beam quality M
2 value is 2.2. 相似文献
945.
A dual-wavelength continuous-wave (CW) diode end-pumped gadolinium scandium aluminum garnet (Nd:GSAG) laser that generates
simultaneous laser action at the wavelengths 1061 and 942 nm is demonstrated. A total output power of 589 mW (476 mW at 1061
nm and 113 mW at 942 nm) for the dual-wave-length was achieved at the incident pump power of 18.2 W. The M
2 values for 942 and 1061 nm lights were found to be around 1.18 and 1.37, respectively. 相似文献
946.
947.
Melodic contour identification was measured in cochlear implant (CI) and normal-hearing (NH) subjects for piano samples processed by four bandpass filters: low (310-620 Hz), middle (620-2480 Hz), high (2480-4960 Hz), and full (310-4960 Hz). NH performance was near-perfect for all filter ranges and much higher than CI performance. The best mean CI performance was with the middle frequency range; performance was much better for some CI subjects with the middle rather than the full filter. These results suggest that acoustic filtering may reduce potential mismatches between fundamental frequencies and harmonic components thereby improving CI users' melodic pitch perception. 相似文献
948.
Li Y Zhang G Kang HY Liu S Han D Fu QJ 《The Journal of the Acoustical Society of America》2011,129(6):EL242-EL247
Cochlear implant (CI) users' speech understanding may be influenced by different speaking styles. In this study, speech recognition was measured in Mandarin-speaking CI and normal-hearing (NH) subjects for sentences produced according to four styles: slow, normal, fast, and whispered. CI subjects were tested using their clinical processors; NH subjects were tested while listening to a four-channel CI simulation. Performance gradually worsened with increasing speaking rate and was much poorer with whispered speech. CI performance was generally similar to NH performance with the four-channel simulation. Results suggest that some speaking styles, especially whispering, may negatively affect Mandarin-speaking CI users' speech understanding. 相似文献
949.
For an inhomogeneous quasilinear hyperbolic system of diagonal form, under the assumptions that the system is linearly degenerate and the C^1 norm of the boundary data is bounded, we show that the mechanism of the formation of singularities of C^1 classical solution to the Goursat problem with C^1 compatibility conditions at the origin must be an ODE type. The similar result is also obtained for the weakly discontinuous solution with C^0 compatibility conditions at the origin. 相似文献
950.
Trivalent dysprosium ions (Dy3+) doped strontium molybdate (SrMoO4) phosphors were synthesized by solid-state reaction and their photoluminescence (PL) properties were investigated. X-ray powder diffraction (XRD) analysis confirmed the formation of SrMoO4:Dy3+. PL measurements indicated that the phosphor exhibited intense emission at 482, 490 (4F9/2→6H15/2) and 575 nm (4F9/2→6H13/2) under UV excitation. The effect of the doping concentration of Dy3+in SrMoO4:Dy3+ on the PL was investigated in detail. Na+ ion was a good charge compensator for SrMoO4:Dy3+. 相似文献