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In this letter, intracavity frequency-tripling of a diode-end-pumped passively Q-switched Nd:YAG/Cr4+:YAG composite laser has been demonstrated for the first time. Under the absorbed pump power of 7.2 W, the maximum UV output power of 110 mW is obtained with the beam quality parameter M2 of 2.95. The minimum pulsewidth and the highest repetition rate are 23.9 ns and 19.6 kHz, respectively. The corresponding single pulse energy and pulse peak power are 5.6 μJ and 0.23 kW. The fluctuation of the average output power at 110 mW within an hour operation is tested and determined to be 4.7%.

The performance of a diode-pumped passively Q-switched Nd: Lu0.5Y0.5VO4 laser at 1.34 μm with Co2+ :LaMgAl11O19(Co2+ :LMA) crystal as the saturable absorber was demonstrated for the first time to the best of our knowledge. Under the incident pump power of 8.18 W, the maximum average output power of 260 mW was achieved with a T = 15% output coupler. The minimum pulsewidth was 154.8 ns, corresponding to the pulse repetition frequency of 163.7 kHz.

It has been demonstrated that shared cavity optical parametric oscillator (OPO) could improve power stability in comparison with that of coupled cavity OPO. By theoretically calculating the spectral transmissions induced by the etalon effect, it has been found that the shared cavity OPO had much wider transmission bandwidth than that of coupled OPO. The corresponding experimental results agreed with the theoretical analysis. Furthermore, the OPO and fundamental laser resonator have nearly the same longitudinal mode spacing in the shared cavity configuration. The above two factors can account for the improved performance of the shared OPO operation.

To summarize the clinical and imaging features of malignant tumors in parotid gland.Four hundred and twelve cases were collected in the department of oral and maxillofacial surgery and department of otolaryngology headneck surgery of general hospital of Chinese PLA and department of oral and maxillofacial surgery of first affiliated hospital of Dalian medical university.The top three malignant tumors were mucoepidermoid carcinoma, adenoid cystic carcinoma and acinic cell carcinoma in parotid gland. Of all the collected cases, 73.1% had certain symptoms or recent rapid growth, 58% had tough quality, 66.2% had poor mobility, 32.3% had unclear boundary and 36.8% had pain. Of all cases with imaging examination, 74.2% and 68.7% demonstrated irregular shapes in CT and ultrasound imaging, respectively. The accuracy was 83.7% and 91.8% for fine-needle aspiration cytology and frozen section examination in diagnosis, respectively. The accuracy was 79.4% for frozen section examination in diagnosis of highly malignant tumors in parotid gland.There are diverse pathological types of malignant tumors in parotid gland. The clinical and imaging features are helpful to diagnosis. The accuracy is high in diagnosis of malignant tumors in parotid gland by fine-needle aspiration cytology and frozen section examination.

Purpose: To investigate the regulatory mechanism of miR-218 in human hepatocellular carcinoma (HCC). Methods: qPCR was used to compare the expression levels miR-218 among six hepatocellular carcinoma cell lines and normal liver tissues. After transfecting MHCC97L cells with either miR-218 mimics or miR-218 inhibitor, western blotting was used to examine the expressing patterns of cyclinD1, p21, and PTEN/AKT/PI3K signaling pathway-related proteins. MTT and colony forming assay was used to assess the capability of cell proliferation. Bioinformatic method was applied to predict the binding of miR-218 on HoxA10, and western blotting was used to examine the modulatory effect of miR-218 AND HoxA10 on PTEN/AKT/PI3K pathway in HCC. Results: The expression levels of miR-218 were frequently lower in HCC cell lines than in normal liver tissues. Over-expression of miR-218 in HCC cells significantly decreased cell proliferation whereas inhibiting miR-218 promoted cancer cell proliferation. Western blotting analysis demonstrated that tumorigenesis related protein cyclin D1 and p21, as well as PTEN/AKT/PI3K signaling pathways were actively modulated by miR-218 in HCC cells. The expression of endogenous HoxA10 was also down-regulated by miR-218 over-expression, and silencing HoxA10 directly activated PTEN in HCC cells. Conclusion: Modulation of miR-218 actively affected HCC cancer cell development. The regulatory mechanism of miR-218 in HCC cells was acting through PTEN/AKT/PI3K pathway and possibly associated with HoxA10.

With a non-critically phase-matched KTA crystal, a high-power intracavity optical parametric oscillator (IOPO) driven by a diode-side-pumped acousto-optically Q-switched Nd:YAG laser has been realized. The maximum average output power of 13.6 W at the signal wavelength of 1534 nm and 3 W at the idler wavelength of 3472.7 nm were obtained with the repetition rate of 18 kHz, giving the optical–optical conversion efficiency of about 5.7% from diode-power at 808 nm to OPO signal output, which was the highest conversion efficiency for intracavity KTA OPO with diode-side-pumping configurations to our best knowledge. At the highest output power of 13.6 W, the signal pulse duration of 5.46 ns was obtained, corresponding to the single pulse energy of 756 μJ and peak power of 138 kW, respectively.

In this article, we demonstrated the acousto-optical Q-switching performance of a high-power diode-pumped Nd:GGG laser. The maximum average output power of 2.56 W was obtained at the repetition rate of 15 kHz, and the minimum pulse width of 21 ns was obtained under the pump power of 9.18 W, the peak power and the pulse energy were calculated to be 11.4 kW and 253.6 μJ. The conversion efficiency of the output power from CW to Q-switching operation was amounted to 60.8%.

In this article, we demonstrated the continuous wave (cw) performance of a high-power diode-pumped Nd:GGG laser. The maximum output power of 13.2 W was obtained under the incident pump power of 28.8 W, giving the optical conversion efficiency of 49.5% and the slope efficiency of 51.5%. And the intrinsic loss of Nd:GGG crystal was measured to be 0.86% cm-1 in our experiment.

An eye-safe, high-repetition-rate, single-resonant nanosecond intracavity optical parametric oscillator (IOPO), based on a non-critically phase-matched KTA crystal driven by a diode-end-pumped acousto-optically Q-switchedNd:YVO4 laser, was demonstrated for the first time to our knowledge. With an absorbed pump power of 11.3 W, 1.1 W average power and 2.5 ns pulse width at the signal (1534 nm) wavelength for 30-kHz repetition rate are synchronously achieved with the 25 mm long KTA crystal. The corresponding peak power and single pulse energy are estimated to be up to 14.7 kW and 36.7 μJ. The conversion efficiency from diode laser power to OPO signal output power was 9.8% and the corresponding slope efficiency was 15.4%.

We have demonstrated an efficient diode-pumped passively Q-switched Nd:YVO4 laser at 1342 nm by using an uncoated Co2+:LaMgAl11O19 (Co2+:LMA) crystal as the saturable absorber. With the absorbed pump power of 11.7 W, the pulse width could be as low as 42 ns, with a corresponding average output power of 580 mW. At around 40 kHz repetition rate, the energy of a single Q-switched pulse was estimated to be about 14.5 μJ and the peak power was 346 W. The passive Q switching operation for the Co2+:LMA in different polarization states was also investigated.

Investigation of acetone extract of the leaves and stems of Daphne feddei afforded three new phenylpropanoids, feddeiketones A-C (1-3), together with nine known phenylpropanoids (4-11). Their chemical structures were elucidated on the basis of spectroscopic methods. Compounds 1-3 were tested for their anti-HIV-1 activities and cytotoxicities against cancer cells. The results showed that compounds 1-3 have modest cytotoxic and anti-HIV-1 activities. A investigação de extrato acetônico de folhas e caules de Daphne feddei forneceu três novos fenilpropanóides, fedeicetonas A-C (1-3), juntamente com nove fenilpropanóides conhecidos (4‑11). Suas estruturas foram elucidadas com base em métodos espectroscópicos. Os compostos 1-3 foram testados com relação as suas atividades anti-HIV-1 e citotoxidades frente a células cancerígenas. Os resultados mostraram que as atividades citotóxicas e anti-HIV-1 dos compostos 1-3 são modestas.

Feddeiphenol A (Ia) and B (Ib), and the new neolignan, feddeiphenol C (II), are isolated from the leaves and stems along with 8 known constituents.

Two new secolignans and one new neolignan, named feddeiphenols A—C (1—3), together with eight known compounds (4—11), were isolated from the leaves and stems of Daphne feddei. Their structures were established on the base of spectroscopic methods, mainly extensive NMR, UV spectroscopy, and MS spectrometry. Compounds 1—11 were tested for their anti-human immunodeficiency virus (HIV)-1 activity and cytotoxicity. The results revealed that compounds 1, 2, 3, 7, and 9 showed therapeutic index (TI) values above 30, respectively, and the other compounds also showed weak anti-HIV-1 activity. Compound 1 showed modest cytotoxic activity. The other compounds also showed weak cytotoxic activity.

We demonstrated the 1.33 microm laser performance with Nd:Gd(3)Al(x)Ga(5-x)O(12) (x = 0.94) (Nd:GAGG) laser crystals for the first time. Continuous-wave (cw) output power of 2.45 W was obtained with the optical-optical conversion efficiency of 21.8% and slope efficiency of 23.3%. In the passive Q-switching regime, the highest output power, the shortest pulse width, largest pulse energy and highest peak power were achieved to be 326 mW 18.2 ns, 36.3 microJ and 2.0 kW, respectively, with V(3+):YAG crystal as the saturable absorber.

To analyze the reasons and related factors of failures in the treatment of intertrochanteric fracture with dynamic hip screw (DHS) and to increase the therapeutic level of intertrochanteric fracture.All the 78 cases of intertrochanteric fractures were treated with dynamic hip screws from Dec. 1998 to Dec. 2007 included 42 males and 36 females with an average age of 62 years old ranging from 26 to 85 years. The disease course was from 1 to 49 hours (means 4 hours). According to Evans-Jensen classification of intertrochanteric fracture, 4 cases were type IA, 24 cases were type IB, 13 cases were type IIA, 22 cases were type IIB, 11 cases were type III, 4 cases were type IV. The fracture were fixed with dynamic hip screws following AO operative standard. To analyze the reasons and related factors of the 12 failed cases involving femur head and neck cut-off, tail pin exit, coxa vara, screw loosening, compress screw slip out of the tube, fracture displacement, respectively.All the cases were followed up for 13 months to 7 years with an average of 36 months, 12 cases were failed including 4 cases of femur head and neck cut-off, 1 case of coax vara, 2 cases of compress screw slip out of the plate tube, 2 cases of screws loosening, 2 cases of tail pin displacement 1 case of great trochanter fracture displacement.For intertrochanteric fracture, to interfix with dynamic hip screw is an effective method, the choice of indication, the type of fracture, the bone mineral density and the manipulative technique affect the results.

Sewage sludge taken from Guilin Wastewater Treatment Plant (WWTP) and elemental sufur(S0) were used as the bioleaching medium and substrate respectively. Acidification effect of sewage sludge, activity of bioleaching microorganism and removal rate of heavy metals were investigated at various temperatures from 10℃ to 40℃ in the bioleaching process. Where Bioleaching experiments were process was operated at 3g•L-1 S0 and 1.0L•min-1 aeration rate. An indigenous Acidithiobacillus thiooxidans was the bioleaching dominant bacteria in the process. The results showed that acidification rate and bacterial activity increased with temperature rising in the temperature range of 10℃~30℃. The optimum temperature range for bioleaching bacteria growth was 20℃~30℃. The activity of bioleaching microorganism was the highest at 28.9℃ and sulfate ions yield was 461.66(mg•L-1)•d-1, To achieve the treatment requirements and low operation energy consumption, the proper temperature for bioleaching engineering application should be controlled at 20℃. Under this condition, the removal rates of Cu, Zn and Cd were 47.45％、77.07 and 80.57％respectively after 5-day bioleaching. The residual concentrations of Cu, Zn and Cd in the treated sludge met with the national standard for sludge agriculture use in China.

Pot experiments were conducted to study the effects of 8 fertilizers (NH4Cl, NH4NO3, Ca(NO3)2, CO(NH2)2, Ca(H2PO4)2, KH2PO4, K2SO4 and KCl) on Ni uptake and distribution by rice. The results indicated that nitrogen and potassium fertilizers had little effect on the biomass and yield of rice, while the phosphate fertilizers significantly increased the biomass and yield of rice. The total amounts of Ni in rice were decreased by 12.3% - 38.8% after fertilizers were applied. Applying NH4Cl, Ca(H2PO4)2, K2SO4 and KCl significantly increased the concentration of Ni in the aerial parts of rice, whereas the rest 4 fertilizers decreased the concentrations of Ni in the aerial parts of rice. The concentration of Ni in the grain under maturity stage were 6.958 - 13.227 mg kg-1 after fertilizer were applied, which increased by 41.03% - 168.11%, and had significantly exceeded the national food heavy metal limits hygienic standard (0.4 mg kg-1). This study suggests that fertilizer application significantly increased the uptake of Ni of grain, and the effects of 8 fertilizers in the order: K2SO4＞KCl＞Ca(NO3)2＞NH4Cl＞CO(NH2)2＞KH2PO4＞NH4NO3＞Ca(H2PO4)2.

The performance of a diode-end-pumped passively Q-switched dual-wavelength Nd:GGG laser operating at 932.9 and 936.5 nm with V(3+):YAG as the saturable absorber was demonstrated for the first time to the best of our knowledge. The maximum dual-wavelength average output power of 150 mW was achieved with a T = 2% output coupler under the absorbed pump power of 2.55 W, corresponding to the optical-to-optical conversion and slope efficiency of 5.9% and 8.0%, respectively. The minimum pulse width was 395 ns with the pulse repetition frequency of 140 kHz, which was attained with a T = 5% output coupler under the absorbed pump power of 2.55 W.

Cooling-air grinding is one of important green grinding. Cooling-air grinding performances for 40Cr are test in this paper using cooling-air generator. Main performance influencing factors are test and analyzed, such as air temperature, wheel granularity, amount of feed and so on. Cooling-air grinding results shows that roughness of surface of test pieces can reach precise grinding standard. So cooling-air grinding can replace traditional grinding in this experiment. This study for the promotion of cooling-air grinding application technology has important significance for reference.Copyright © 2010 by ASME

This paper presented a marginal method allocating transmission losses to bilateral exchanges in the context of bilateral trading, based on the special relation between marginal loss comparative values for different slack buses. The advantage of this method is that the sharing results are irrelevant to the selection of slack bus, which is able to intuitively reflect the transmission distance of bilateral exchange. Through Equivalent Bilateral Exchanges (abr. EBE) principle it is extended the application to loss allocation in the power pool. Finally, it is used in a Chinese provincial power grid to solve the issue of transmission loss allocation to bilateral exchanges. Results illustrate the feasibility and effectiveness of the method.

The performance of a diode-pumped passively Q-switched Nd:Gd(0.5)Y(0.5)VO(4) laser at 1.34 microm with V(3+):YAG as the saturable absorber was demonstrated for the first time to the best of our knowledge. The focal lengths of thermal lens in the diode-end-pumped Nd:Gd(0.5)Y(0.5)VO(4) laser for the 1.34 microm transition was experimentally investigated, with the corresponding proportion constant estimated to be approximately1.5x10(4) W/mm. For the passive Q-switching operation, the maximum average output power of 0.96 W was achieved under the pump power of 7.28 W, corresponding to optical-to-optical conversion and slope efficiency of 13.2% and 17.6%, respectively. The minimum pulse width attained was 47.8 ns with the pulse repetition frequency of 76 kHz, with the single pulse energy and peak power estimated to be 8.7 microJ and 182 W, respectively.

The title compound, C(20)H(19)N(3)O(2), was obtained by the condensation of 4-(dimethyl-amino)benzaldehyde with 3-hydr-oxy-2-naphthohydrazide. The mol-ecule is approximately planar, with an intra-molecular N-H⋯O hydrogen bond involving the imino H atom and the hydr-oxy O atom. The dihedral angle between the benzene ring and the naphthyl mean plane is 2.72 (13)°. In the crystal structure, symmetry-related mol-ecules are linked by inter-molecular O-H⋯O hydrogen bonds, forming chains propagating in the c-axis direction.

The title compound, C(15)H(13)ClN(2)O(2)·CH(4)O, consists of a 4-chloro-N'-(4-meth-oxy-benzyl-idene)benzohydrazide (CMB) mol-ecule and a methanol mol-ecule of crystallization. It was obtained by the condensation of 4-meth-oxy-benzaldehyde with 4-chloro-benzohydrazide. In the CMB mol-ecule, the dihedral angle between the two benzene rings is 50.1 (3)°. The methanol mol-ecule is linked to the CMB mol-ecule through O-H⋯O and O-H⋯N hydrogen bonds. In the crystal, CMB mol-ecules are linked through inter-molecular N-H⋯O hydrogen bonds, involving the methanol mol-ecule, forming chains propagating along [010].

为进一步揭示硝酸还原酶（nitratereductase，NR）活性的调控机制及其与植株体内硝酸盐含量的关系。本试验在正常供氮（15mmolL—N03-）和缺氮（7．5mmolL—N03-）条件下，以氮高效（H1：742和H2：Xiangyou15）和氮低效（L1：814和L2：H8）油菜基因型为研究材料，通过NR活性的专性抑制剂处理，研究NR活性和硝酸盐含量的基因型和氮水平差异。结果表明，NR专性抑制剂处理可以显著降低叶片NR活性，正常供氮和缺氮条件下分别降低53．0％和57．6％，但对叶片硝酸盐的含量没有显著影响。正常供氮条件下的NR活性和硝酸盐含量比缺氮条件下分别高46．9％和16．4％。氮高效油菜基因型的硝酸盐含量显著低于氮低效基因型。H2的NR活性（NRA。。。）显著高于氮低效基因型的本质原因是其主效基因（＂f以）的相对表达量高于氮低效基因型。本研究充分表明NR活性和硝酸盐含量存在明显的基因型和氮水平差异，一定程度的NR活性变化对植株体内硝酸盐的含量并没有显著的影响。

Gold nanorods (AuNRs) can be successfully co-assembled with Ag nanowires (AgNWs) to form a kind of AuNR-AgNW nanocomposite by electrostatic attraction, in which the AuNRs are arranged along the long axial direction of the AgNWs with a preferential string-like alignment. The assembled AuNR-AgNW nanocomposites are then further embedded within polyvinyl alcohol (PVA) nanofibers by electrospinning, by which both AuNRs and AgNWs can be stabilized and arranged along the axis of polymer nanofibers. When the polymer nanofibers are aligned by collecting on a copper mesh with a woven structure, the AuNR-AgNW nanocomposites assembled within the electrospun nanofibers are also arranged. The influences of the AuNR-AgNW assemblies with different amounts of AuNRs attached on AgNWs on the optical properties and surface enhanced Raman scattering (SERS) enhancement have been investigated. The resulting AuNR-AgNW/PVA electrospun mats show red-shifted and broader absorption bands and higher SERS performances compared with the normal casting films with randomly dispersed AuNRs and AgNWs, or electrospun mats with monometallic components, due to the order alignment of AuNR-AgNW nanocomposites on a large scale.

We demonstrated a diode-pumped continuous wave and passively Q-switched Nd:Lu(x)Y(1-x)VO4 laser at 1.34 μm with V3+:YAG as the saturable absorber. The crystal Nd:Lu(x)Y(1-x)VO4 with equal ionic ratio (x = 0.5) shows better laser performance. The maximum continuous wave output power of 1.45 W was obtained with the optical efficiency of 20.1% and the slope efficiency of 24.5%. For the pulsed operation, the minimum pulse width achieved was 42 ns with the pulse repetition frequency of 142 kHz, and the single pulse energy and the peak power were estimated to be 6.62 μJ and 157.6 W, respectively.

A comparative study of a frequency-doubling 532 nm laser based on gray-tracking-resistant KTP (GTR-KTP) and conventional KTP is presented. The intracavity GTR-KTP was proved to have better temperature characteristics than that of conventional KTP. Within the normalized output power variation range of 0.8-1.0, GTR-KTP has a temperature tolerance of 35 degrees C, broader than the 21 degrees C obtained with conventional KTP. Under the laser diode (LD) pump power of 180 W, the maximum average output power at 532 nm was 40.6 W for GTR-KTP at a repetition frequency of 10 kHz. In the case of conventional KTP, the maximum available LD pump power was limited to 150 W, with the corresponding maximum green average output power of 27.2 W.