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We report on a high-peak-power electro-optically Q-switched laser emitting a near-diffraction-limited beam profile at 1064 nm by using a gradient-doped Nd:YAG crystal. The gradient-doped crystal features a unique combination of a reduced thermal lens effect through effectively spreading the heat load distribution within its volume. Its performance is compared with those of Nd:YAG crystals with uniform volume doping distribution operating in the Q-switched regime with the same laser configuration, demonstrating the higher average and peak power achievable with the gradient-doped crystal. The maximum average output power amounts to 6.9 W at a pulse repetition rate of 2 kHz, which corresponds to a maximum peak power of ∼585kW. Compared to homogeneous dopant crystals, the slope efficiency and average output power increased by 30.8% and 21.1%, respectively.

Magnesium lithospermate B (MLB) is a new drug marketed in China to treat angina, but its low oral bioavailability limits its clinical application to the intravenous route. Paradoxically, orally administered low-dose MLB was found to alleviate kidney injury in diabetic nephropathy (DN) rats, but its mechanism of action remains unknown. In recent years, the kidney-gut axis has been suspected to be involved in kidney damage pathogenesis, potentially representing a non-classical pathway for pharmacologic intervention. To ascertain whether MLB targets the kidney-gut axis, streptozotocin (STZ)-treated mice were prepared as a mouse model of DN. The STZ mice were treated with MLB (50 mg kg−1d−1, p.o.) for 8 weeks. Twenty-four-hour urinary albumin was detected to mirror kidney function. At week 4, 6, 8, feces were collected; bile acids (BAs) were quantified to examine the alterations in the BA metabolic profiles, and bacterial 16S rRNA gene fragments were sequenced to identify alterations in gut microbial composition. In STZ mice, 24-h urinary albumin levels and total fecal BAs, especially cholic acids (CAs) and deoxycholic acids (DCAs) were greatly increased, and the gut microbiome was dramatically shifted compared with control mice. Oral administration of MLB significantly decreased 24-h urinary albumin levels and total BAs, CAs and DCAs, and reversed CA:TCA (taurocholic acid) and DCA:CA ratios. It also changed the microbiome composition in STZ mice based on operational units. Thus the therapeutic effect of MLB on kidney injury might be attributed (at least partially) to its ability to modulate the disordered gut microbiome and BA metabolism.

Cf/SiO2 composites were prepared by slurry impregnation-hot pressing process, and their mechanical properties, microstructure and surface morphologies were then investigated. The results indicated that the composites showed the best mechanical properties, and the tensile strength, bending curvature, compression strength were 58MPa, 170MPa, 256MPa respectively. XRD spectrums showed that fused quartz appeared no crystallization during the process. Also from the TEM analysis, we can see that the Cf/SiO2 composites exhibited the best compactness. All the tests were carried out on the composites autoclaved at 1400°C for 60min, according to which the best hot pressing process was concluded.

The vacuum-sintering technology was adopted to prepared Si3N4-SiC composite ceramic, a type of Radar Wave-Absorbing materials (RAW). The mechanical performances of the composite materials were tested and the influences of SiC powers on the mechanics performances and microstructure of Si3N4 ceramics were investigated. The results show that the sintering density, the content of size ofβ-Si3N4 and the strength of Si3N4-SiC all decrease along with the increase of SiC powers in sample, compared with the pure matrix Si3N4 .Meanwhile, Relationship between SiC content and relative permittivity of Si3N4-SiC within the frequency range of 8.2–12.4 GHz (X-band) was studied. The average of relative permittivityεof Si3N4-SiC increased from 7.878 to 13.88 and the average of dielectric loss tanδincreased from 5.6×10-3 to 0.7869 when the content of SiC increased from 0 to 15 wt.%. The excellent microwave absorbing abilities of Si3N4–SiC ceramic were attributed to the interfacial polarization at interface between Si3N4 and SiC and at grain boundary between SiC nanocrystals.

Quartz-based composites reinforced by acupuncture quartz fibers were prepared by liquid phase infiltration-in situ solidification process. Effects of different molding processes on the density, micro-structure, phase structure and mechanics properties of the composites were studied. The experimental results show that the composite materials prepared by the silica slurry as matrix and 10% silica sol as the interface layer have better performance: the density increased from 0.74g/cm3 to 1.58g/cm3; the tensile strength, flexural strength and compressive strength reached 32.2MPa, 72.6MPa and 116MPa respectively; it is worth noting that the micro-structure of the material is uniform and compact, and the fracture mode of the material is ductile fracture with the pull out of the fiber.

Quartz fiber composites filled with nanosized SiO2 were prepared by sol-gel method with vacuum impregnation , supercritical drying and surface modification. The silica sol for vacuum impregnated were made from tetraethyl orthosilicate (TEOS), anhydrous ethanol, water and acid catalyst as the starting materials. The water adsorption rate, apparent porosity and electrical properties of composites were investigated by means of archimedes method and waveguide method while the surface area and pore size of the aerogel samples were tested by BET, the mechanism of hydrophobicity was also discussed. The results showed that the moisture absorption rate of products was decreased to 1.21% from 17.36% that without filled with nanosized SiO2, with a decreasing range of 93%. Additional coating could make the rate even as low as 0.052%.The dielectric constant had no significant change while the loss tangent decreased from 3.1╳10-3 to 1.4╳10-3,with a decreasing range of 51.2%.

Laser surface hardening is widely used. The complexity of the surface restricts its application. To solve this problem, it is necessary to study the path of the laser spot. By comparison the difference of CNC cutting machine and laser processing machines, the control system of laser spot is built. And the method of alignment for work coordinate system is obtained. NC programming model of the laser beam is established using CAM software. The change of area of spot when laser beam projected to the different normal angles surface was analyzed, and it is get the relationship of normal angles and feed rate. The complex surface laser surface hardening is realized.

Edwardsiella tardahas become one of the most severe pathogens in aquaculture industries throughout the world; therefore, a specific and rapid identification method for this bacterium is urgently needed. In the present study, a novel loop-mediated isothermal amplification (LAMP) was developed by targeting the upstream region of the hlybgene of E. tarda, which was then named as UH-LAMP. The Mg2+concentrations, the reaction temperature, and the reaction time of UH-LAMP were optimized to 10 mM, 65°C, and 45 min, respectively. The detection limit of the UH-LAMP was 100-times higher than that of conventional polymerase chain reaction (10 versus 1000 CFU/test). Furthermore, the new UH-LAMP assay showed no cross-reactivity to the E. ictaluribelonging to the other species in the genus Edwardsiella. The high specificity of the assay was also confirmed by testing the nine strains of E. tardacollected from different geographical locations and the other 20 bacteria species. The assay can be performed in a simple water bath or a heat block and the detection result can be visualized by adding a fluorescent reagent to the reaction mixture. Taken together, our preliminary results indicate that this UH-LAMP assay provided a rapid, sensitive, and species-specific diagnostic tool for E. tardaand can easily be applied for the diagnosis under clinical or onsite conditions. Received December 10, 2012; accepted February 22, 2013

AbstractEdwardsiella tardahas become one of the most severe pathogens in aquaculture industries throughout the world; therefore, a specific and rapid identification method for this bacterium is urgently needed. In the present study, a novel loop-mediated isothermal amplification (LAMP) was developed by targeting the upstream region of the hlybgene of E. tarda, which was then named as UH-LAMP. The Mg2+ concentrations, the reaction temperature, and the reaction time of UH-LAMP were optimized to 10 mM, 65°C, and 45 min, respectively. The detection limit of the UH-LAMP was 100-times higher than that of conventional polymerase chain reaction (10 versus 1000 CFU/test). Furthermore, the new UH-LAMP assay showed no cross-reactivity to the E. ictaluribelonging to the other species in the genus Edwardsiella. The high specificity of the assay was also confirmed by testing the nine strains of E. tardacollected from different geographical locations and the other 20 bacteria species. The assay can be performed in a simple water bath or a heat block and the detection result can be visualized by adding a fluorescent reagent to the reaction mixture. Taken together, our preliminary results indicate that this UH-LAMP assay provided a rapid, sensitive, and species-specific diagnostic tool for E. tardaand can easily be applied for the diagnosis under clinical or onsite conditions.Received December 10, 2012; accepted February 22, 2013

Hydrochloric acid doped polyaniline and camphor sulfonic acid doped polyaniline were prepared by oxidative chemical polymerization and grinding, respectively. The structures of polyaniline samples were measured by Fourier transform infared spectroscopy. The Seebeck coefficient and electrical conductivity of the composites were investigated as protonic acid content in the temperature range from room temperature to 380K. The highest electrical conductivity of the 1M hydrochloric acid doped polyaniline reaches 5.57×102S/m at 320K, and the mass ratio of 1:1 camphor sulfonic acid doped polyaniline reaches 5.97×102S/m at 380K. This work suggests that a new method improves the thermoelectric properties of conducting polymers.

To gain insight into the molecular events of lymph node metastasis of human gastric carcinoma.

Multiple organ dysfunction syndrome (MODS) is a major cause of mortality in PICUs in industrialized countries. As developing countries become more advanced, PICU care comes into reach. The aim of this study was to examine MODS in a PICU in China in comparison with other countries.

The infrared (IR) absorption of the amide I band for the loop structure may overlap with that of the α-helices, which can lead to the misassignment of the protein secondary structures. A resolution-enhanced Fourier transform infrared (FTIR) spectroscopic method and temperature-jump (T-jump) time-resolved IR absorbance difference spectra were used to identify one specific loop absorption from the helical IR absorption bands of horse heart cytochrome c in D2O at a pD around 7.0. This small loop consists of residues 70–85 with Met-80 binding to the heme Fe(III). The FTIR spectra in amide I′ region indicate that the loop and the helical absorption bands overlap at 1653cm−1 at room temperature. Thermal titration of the amide I′ intensity at 1653cm−1 reveals that a transition in loop structural change occurs at lower temperature (Tm=45°C), well before the global unfolding of the secondary structure (Tm≈82°C). This loop structural change is assigned as being triggered by the Met-80 deligation from the heme Fe(III). T-jump time-resolved IR absorbance difference spectra reveal that a T-jump from 25°C to 35°C breaks the Fe-S bond between the Met-80 and the iron reversibly, which leads to a loop (1653cm−1, overlap with the helical absorption) to random coil (1645cm−1) transition. The observed unfolding rate constant interpreted as the intrachain diffusion rate for this 16 residue loop was ∼3.6×106s−1.

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