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GGG70L is a kind of cold-working die steel widely used in large automobile cover parts die. In order to ensure the life of the die, laser quenching process is usually used to form a certain hardened layer at a specific part of the die. In this paper, the changes of microstructure and hardness of ductile iron GGG70L after laser quenching were studied through a large number of process experiments, and the influence of quenching process parameters on the microstructure and properties of GGG70L was obtained. The relationship between the depth of hardened layer and the laser energy density is established and a quadratic function relationship was found between the two. It is found that both higher hardness and deeper hardening depth can be obtained when the energy density is 24-28 (J/mm2). The finite element model of the laser quenching process of GGG70L was established, and the temperature of the hardened zone and its evolution law during the laser quenching process were studied numerically.

临床决策是医疗活动的重要组成部分，医患共同决策（SDM）是一种鼓励医生与患者共同参与的新兴决策模式，是指将患者纳入医疗决策过程中，医生与患者就某一医疗决策多种选择的利弊进行充分沟通，结合患者个人喜好、社会与文化背景以及教育与经济水平等多方面因素，最终医患双方做出共同决策。国外已有多个学科将SDM应用于临床实践。SDM在我国心血管病领域推进也是可行的，但尚存在诸多问题。随着这些问题的逐步解决，SDM 可以进一步改善临床决策过程，对优化治疗方式的选择、改善疗效都具有积极的作用。.

报道1例乳腺高细胞亚型乳头状癌，患者为70岁女性，左乳肿块。组织学显示癌组织呈实性乳头状结构，被致密的纤维结缔组织分隔为巢状排列，癌细胞形态温和，呈立方状和高柱状排列，胞质嗜酸性或透明状，核呈圆形或卵圆形，染色质淡染，核膜清晰，核沟易见，并可见一些小核仁，轻度异型，未见明显的核分裂象和核内假包涵体。免疫表型示癌细胞特征性表达细胞角蛋白（CK）5/6、Calretinin；而甲状腺相关标志物甲状腺转录因子1（TTF1）、甲状腺球蛋白（TG），神经内分泌标志物嗜铬粒素A、突触素及肌上皮标志物p63、Calponin、S-100蛋白均呈阴性，Ki-67阳性指数2%。雌激素受体、孕激素受体及HER2阴性，分子分型提示为基底细胞样型。分子遗传学检测结果提示第15号染色体IDH2（p.R172）点突变，同时PIK3CA及PDCD1伴随突变。结果提示乳腺高细胞亚型乳头状癌是一种罕见的原发于乳腺的低度恶性肿瘤，诊断时结合特征性的形态学、免疫表型及分子遗传学特征，并与组织形态学相似的转移性甲状腺癌及其他乳腺乳头状病变相鉴别。.

To improve the photocatalytic performance of tungsten oxide, attapulgite, used as supporter and adsorbent, was combined with tungsten oxide nanoparticles to form a kind of new photocatalyst. The photocatalyst (attapulgite/WO3) was prepared in a mild condition at 60oC in an attapulgite/WCl6/ethanol/water system through alcoholysis and hydrolysis. The amount of WCl6 added in the chemical solution has an important influence on the morphology and structure of the products based on field emission scanning electron microscope and X-ray powder diffraction characterization. The photocatalytic activities of all the products were tested by degrading rhodamine B with the existence of H2O2. The result shows that the obtained attapulgite/WO3 nanocomposites have a great improvement in photocatalytic activity.

In this work, the Nb-based Nb42Ni40Co18¹xZrx (x = 0, 4, 12) and Nb42Ni32Co6Zr12M8 (M = Ta, Ti, Zr) amorphous alloy ribbons were successfully prepared by single roller melt-spinning technique. These amorphous alloys exhibit high thermal stability with the crystallization temperature (Tx) exceeding 850K. It has been found that Tx of the Nb42Ni40Co18 alloy decreased with Zr addition, while hydrogen permeability increased linearly with Zr content. The hydrogen permeability of the Nb42Ni40Co18 ,N b42Ni40Co14Zr4 ,N b42Ni40Co6Zr12 and Nb42Ni32Co6Zr20 amorphous alloys at 673K are 0.03 © 10 ¹8 , 0.23 © 10 ¹8 , 0.69 © 10 ¹8 and 1.40 © 10 ¹8 mol·m ¹1 ·s ¹1 ·Pa ¹1/2 , respectively. It is noticed that hydrogen permeability of the Nb42Ni32Co6Zr20 alloy is comparable with that of Pd­23%Ag alloy (1.14 © 10 ¹8 ). Meanwhile, permeability of the above mentioned alloy decreased to 60% of the initial value while it still maintains amorphous structure after 24h long term durability test. Both thermal stability and hydrogen permeability are enhanced by substituting 8at% Ni with Ta or Ti in the Nb42Ni40Co6Zr12 alloy. The present result indicates that the Nb-based amorphous alloys possess the potential of applying as a kind of hydrogen permeable membrane at high temperature. [doi:10.2320/matertrans.MF201310]

The copper mold casting method is now commonly used for preparing bulk metallic glasses (BMGs). In the present work, it was found that, by employing the copper mold casting method, Pd77.5Cu6Si16.5 (at. pct) glassy rods with 1-mm diameter could be prepared, while the ϕ2-mm Pd77.5Cu6Si16.5 casting rod possesses some crystalline phases embedded within the glass matrix, confirming that the critical size of the glassy alloy is about 1 mm. By melt purification with fluxing treatment, the critical size of the glassy rod prepared by copper mold casting is increased to 4 mm. Based on thermal property analysis, it was found that melt purification by the fluxing method can greatly enhance the thermal stability and increase the glass forming ability (GFA) of the Pd-Cu-Si alloys. The as-prepared ϕ4-mm Pd-Cu-Si glassy rod exhibits a reduced glass transition temperature (T rg ) of 0.599, a supercooled liquid region (ΔT) of 74 K (74 °C), and a γ parameter of 0.419.

The corrosion wear behaviours of an aluminium alloy 2024Al flat specimen against a 440C stainless-steel counter ball specimen were evaluated in artificial seawater by using a ball-on-flat configuration with 300 μm amplitude at room temperature for 1 h. Reference experiments were also performed in distilled water. The worn surface of the specimen was observed using scanning electron microscopy. The three-dimensional morphology and wear volume loss were determined using a non-contact optical profilometer. Potentiodynamic anodic polarization was used to measure the corrosion behaviours of 2024Al before and after the corrosion wear test. The influences of the aqueous medium on the corrosion resistance, coefficient of friction, and wear loss were analysed. Results show that 2024Al exhibits a dominant pitting corrosion mechanism in seawater and corrosion is accelerated by wear. Seawater can reduce the friction coefficient, whereas the wear loss in seawater is higher than that in distilled water, which can be attributed to a higher Cl— percentage. This implies that the wear is accelerated by corrosion. There is a positive synergism between corrosion and wear for 2024Al sliding in seawater. The wear mechanism of 2024Al is dominant corrosion fatigue in seawater due to the distinct electrochemical reaction. The profile of wear concave gradually changes from ‘V’ shape into ‘U’ shape with the increase of load or frequency.

In order to improve the performance of ZnO-based solar cells, highly-ordered hierarchical ZnO nanostructures were design and fabricated. The hierarchical nanostructures were grown on FTO (fluorine doped tin oxide, SnO2:F) glass substrates via a facile, low-temperature, and low-cost chemical route. The morphology and structure of the obtained products has been confirmed by field-emission scanning electron microscopy and X-ray diffraction measurements. The performance investigation of the prepared dye-sensitized solar cells (DSSCs) demonstrates that the hierarchical ZnO nanostructure-based solar cell shows a higher short-circuit current density compared with the ZnO nanowire counterpart. The enhanced current density may be due to the fact that the surface area of the hierarchical nanostructures is increased. These results indicate that hierarchical ZnO nanostructures are more suitable for the application as photoelectrode of DSSCs. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The oriental river prawn (Macrobrachium nipponense) is an important freshwater prawn species in China. We reported the isolation and characterization of 24 novel polymorphic microsatellite loci isolated from genomic DNA in this species enriched by (CA)15 and (CT)15 probes. The variability of these microsatellites were tested on 60 individuals collected from Hongze Lake (China). The average allele number was 15.2 per locus, ranging from 9 to 25. The observed heterozygosity was from 0.1333 to 0.9667 and the expected heterozygosity was from 0.8391 to 0.9570. 9 of the 24 microsatellites did not conform to Hardy–Weinberg equilibrium, whereas all the microsatellite loci have shown a high degree of polymorphism information content (PIC > 0.5). These microsatellites can be used to study economic traits of QTL position, population genetic diversity and the construction of the genetic mapping for Macrobrachium nipponense in the future.

Selective laser melting (SLM) is a precise additive manufacturing process that the metallic powders without binder are melted layer by layer to complex components using a high bright fiber laser. In the paper, Ti-6Al-4V alloy was fabricated by SLM and its microstructure and mechanical properties were investigated in order to evaluate the SLM process. The results show that the microstructure exists anisotropy between the horizontal and vertical section due to the occurrence of epitaxial growth, and the former microstructure seems equal-axis and the latter is column. Moreover, there is little difference in tensile test between the horizontal and vertical sections. Furthermore, the tensile properties of fabricated Ti-6Al-4V alloy by SLM are higher than the forged standard ones. However, the fatigue results show that there are some scatters, which need further investigation to define the fatigue initiation.

Purpose : To investigate the inhibitory effect of the methanol fraction of Dioscorea nipponica Makino ethanol extract (DNM) on melanogenesis both in vitro and in vivo. Methods: Cultured mouse B16 melanoma cell and zebra fish were used to evaluate the melanogenesis inhibitory activity of DNM in vitro and in vivo, respectively. In B16 cells, inhibitory effects on intracellular melanogenesis, tyrosinase activity and reactive oxygen species (ROS) were determined after DNM treatment. In zebra fish, both toxic and antimelanogenic ctivities of DNM on developed larvae were evaluated. Results: In B16 cells, the results show that DNM dose-dependently inhibited melanogenesis at non-toxic concentrations. Surprisingly, however, DNM had no effect on intracellular tyrosinase activity or the amount of the enzyme in B16 cells. On the other hand, DNM showed strong antioxidant activities against cell-free 2,2-diphenyl-1-picryl-hydrazl (DPPH) and 2,2’-azino-bis (3-etnylbenzthiazoline-6-sulphaonic acid) (ABTS+) free radical and intracellular ROS in B16 cells. In zebra fish, DNM significantly and dose-dependently inhibited skin melanogenesis of zebra fish larvae at non-toxic concentrations. Conclusion : The findings demonstrate that DNM inhibits melanogenesis in vitro in B16 melanoma cells and in vivo in zebrafish. Furthermore, DNM exhibits potent inhibition of melanogenesis probably as a result of its antioxidant activity in the cells. Keywords : Dioscorea nipponica, Makino, Melanogenesis, Tyrosinase, Antioxidant, Melanoma, Zebra fish

A finite difference method (FDM) with an analytical truncation boundary condition is developed for the analysis of cyclic H-plane waveguide three-port circulators with an arbitrary shape ferrite post. The method is based on scalar wave equations and the analytical field distribution in the rectangular waveguides. A general boundary field equation for an arbitrarily shaped ferrite or dielectric interface is derived. To verify the validity of the present method, the eigenvalue phases of the cyclic three-port empty junctions and the characteristics of H-plane waveguide Y-junction circulators with lossless, lossy cylindrical, composite and triangular ferrite post are calculated. Good agreements with previously published experimental and theoretical results have been achieved. The performance of a Y-junction circulator with a hexagonal ferrite post and the characteristics of a cyclic three-port circulator with a ferrite rod are also investigated.

The scattering of a plane wave by a magnetized ferrite sphere is rigorously analyzed by a finite-difference time-domain technique with a perfectly matched layer. The field components in the sphere and power–density distribution on the surface of the sphere are obtained. The circulating characteristics of the scattered field due to the magnetized ferrite sphere are observed. The insertion loss and isolation coefficient of the scattering of a magnetized ferrite sphere are presented and compared with the experimental results of a waveguide Y-junction circulator with a ferrite sphere. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 17: 297–300, 1998.

A novel shielded periodic meander line is presented. Its dispersion characteristics are formulated in terms of a rigorous, hybrid-mode representation and Floquet theorem. Some numerical results are included and good agreements compared with other available data are observed. Finally, a quarter-wave rectangular cavity with a shielded meander line is designed. © 1996 John Wiley & Sons, Inc.

A new method for analyzing a millimeter-wave H-plane waveguide Y-junction circulator with a partial height ferrite post is presented. Simple formulas are developed for determining the center frequency of the circulator and the length of the ferrite rod. The lowest mode of operation is not unique and is dependent on the length of the ferrite post. Based on the newly derived formulas, several broadband 3-mm circulators have been designed, assembled, and tested. Good agreement between the analytically obtained performance and experimental results is observed. © 1995 John Wiley & Sons, Inc.

Background Xenon-CT is a quantitive technique for estimating cerebral blood flow. To investigate whether penumbra exists around hematoma, regional cerebral blood flow (rCBF) was measured by Xenon-CT in patients with intracerebral hemorrhage (ICH).

By using the ball-on-flat configuration at 30Hz frequency in SRV tribo-tester with various normal loads and amplitudes, the corrosive fretting wear behavior of a titanium alloy TC11 flat against a high carbon bearing steel counter ball was investigated in artificial seawater and distilled water respectively at room temperature for 1h. The worn surfaces of TC11 were observed by scanning electron microscopy (SEM) and analyzed by energy dispersive spectroscopy (EDS). The influences of the load, amplitude and aqueous medium on the friction coefficient and wear resistance of TC11 were analyzed. It is clear that the friction coefficient curve undulates in the fretting proceeding and fluctuates from 0.2 to 0.6 in the seawater, while it shows better stability in the distilled water which fluctuates from 0.5 to 0.6. The friction coefficient curve gets more stable as the amplitude decreasing in both the aqueous media. Results from the SEM and EDS analysis revealed that compared with that in distilled water, the lubrication surface film formed on the wear scar in the artificial seawater could reduce the friction coefficient greatly, even to 50%. The wear volume-loss of TC11 in the artificial seawater is always lower than that in the distilled water. It demonstrates the dominant roll action of the lubrication of seawater and therefore presents a negative synergy ratio between corrosion and wear. The wear mechanism of TC11 is delamination fatigue associated with abrasion at short amplitude, whereas it is only abrasive wear at long amplitude.

The propagation characteristics of electromagnetic waves in a waveguide tee-junction with various discontinuities are investigated by the finite-difference time-domain technique with the perfectly matched layer. The electromagnetic field components and S-parameters are obtained and compared with experimental data and theoretical data computed by the other method. The effects on the S-parameters caused by the discontinuities in the tee-junction are investigated. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 267–269, 1999.

Xenon-CT is a quantitive technique for estimating cerebral blood flow. To investigate whether penumbra exists around hematoma, regional cerebral blood flow (ICBF) was measured by Xenon-CT in patients with intracerebral hemorrhage (ICH).Xenon-CT was performed on 15 patients with basal ganglia hemorrhage and hematoma volume50 mL. rCBF was measured within 36 h of onset and an average of 13 days later by 27-pixel rings in perihematomal area and its enantiomorph in contralateral hemisphere. Penumbra was defined as rCBF 8-20 mL x 100 g(-1) x min(-1).Average ICH volume was 13 +/- 7 mL (6.4-23.7 mL). First rCBF examination was conducted at 21.7 +/- 9.4 h (5-37 h), second rCBF examination was conducted at 13.4 +/- 1.8 days (11-18 days) after onset. Within 36h of onset, mean perihematomal rCBF was 28.4 +/- 7.8 mL x 100 g(-1) x min(-1); contralateral region was 34.2 +/- 12.2 mL x 100 g(-l) x min(-1) (p = 0.11). Average 13 days after onset, mean rCBF close to hematoma was 19.4 +/- 8.1 mL x 100 g(-1) x min(-1); rCBF in contralateral region was 40.1 +/- 11.3 mL x 100 g(-1) x min(-1) (p0.0001). rCBF in distal perihematomal region was 27.8 +/- 9.5 mL x 100 g(-1) x min(-1); the difference was significant compared to contralateral region (p = 0.0003). One patient's rCBF in area of edema around hematoma was less than 20 mL x 100 g(-1) x min(-1) at first examination. At second examination, 6 patients had same occurrence in region adjacent to hematoma and 2 patients experienced it in distal perihematomal region.Reduced perihematomal rCBF was shown after ICH; this phenomenon lasted at least 14 days. A number of ICH patients experienced penumbra around hematoma.

An experimental 8mm-wave multi-functional transmission system has been set up for the transmission of color TV, telephony, and data in a bi-directional manner. In this paper, the design and performance of this system is presented with regard to detailed system considerations and description. A series of measurements and experiments have been carried out to measure the practical transmission performance, and to observe the transmission quality. At a given bit error rate, the deterioration of signal-to-noise ratio in a nonlinear band-limited channel have been predicted with a MSK modulation. The link availability of this system at different data rates are given in reference to the rainfall distribution of Hong Kong. The experimental results show that the transmission range > 1km for TV signal under clear-air conditions, transmit-receive isolation > 50dB, low bit error rate at a serial data communication, and high quality of TV programs transmission can be observed.

A numerical approach based on the 3D finite-difference method and the analytical results of the fields in waveguides is developed for the analysis of the characteristics of waveguide three-port junctions. The basic two wave equations described by two transverse field components with respect to the direction of the power propagation are derived from the Maxwell Equations in cylindrical coordinates. For the junctions filled with air, there is only one field component in each equation, and generally solving the equation relative to electric field is enough for the obtain of the property of the junction. Two typical cases were analyzed by the approach and the results agree well with the earlier experimental and theoretical results.

An experimental transmission system at 8mm-wave was built up to perform a multi-channel transmission of audio and video signals in frequency reuse, due to space separation and polarization isolation. The features of such an 8mm-wave communication systems is described in details with respect to system construction and performance. Based on carrier-to- noise ratio and the signal level available, the attenuation margin and link availability are evaluated in terms of path length and specific rainfall distribution at Hong Kong. The quality of the demodulated video and audio signals is used for the analysis of co-channel interference and multipath effects. The experiment results show that the polarization isolation is more than 18.5dB, space isolation is more than 24.1dB, and a good quality in transmission of TV programs is observed in frequency reuse situation under a uncritical condition. Finally, a simplified scheme of the application of this system in wharf container dispatching and management is proposed.

Left ventricular end-diastolic compliance (LVEDC) and transmitral flow velocities were measured in 19 patients with coronary artery disease associated with hypertension and 10 normal subjects by LV catheterization and pulsed-Doppler echocardiography. LVEDC was much lower in the patient than in the normal subjects (P less than 0.01). The data showed that abnormal Doppler diastolic function such as elevated late diastolic peak flow velocity (PVA) and decreased LVEDC occurred in the patients at the same time. In addition, the negative correlation of PVA with LVEDC observed in normal controls but not in patients suggested that in patients with impaired diastolic filling, factors other than the decreased LVEDC itself must also participate in the development of diastolic dysfunction.

Forty-one astrocytomas of different grades were studied by means of image analysis technique for measuring DNA content in situ, and in 28 tumors the numbers of nucleolar organiser region (NORs) associated proteins were also determined, and 12 cases of astrocytoma in frontal lobes were followed up. The results showed that the distribution of DNA content in grade I astrocytoma was 2C-4C, the peak values of grade I astrocytoma was 2C; while for grade II, 3C-4C and hypertetraploid. DNA contents of grade III and IV astrocytomas were much higher, their histograms were dispersed with many peaks, the peak values were aneuploid and heteroploid. The data confirm that heteroploid and aneuploid are the marks of malignancy. The grade II astrocytoma which possesses these features has a tendency to higher malignancy. Twenty-eight astrocytomas were stained by Argyrophil (Ag-NOR) for NOR associated proteins. The largest numbers of Ag-NORs were seen in grades III and IV astrocytoma (mean 11.71), and their Ag-NORs were irregular. Grade I astrocytoma possessed the fewest Ag-NORs (mean 6.5) which were small and uniform. The results suggest that the number of Ag-NORs is associated with the differentiation. The prognosis is significantly correlated with the numbers of Ag-NORs and the contents of DNA in astrocytomas.

The influence of the No. II oral contraceptive on platelet function and blood coagulability were studied in 65 women who had taken the drug for 1 to 17 (average 6.7) years. 20 women who hadn't taken any contraceptive served as controls. Results showed that platelet aggregation, adhesive rates, and fibrinogen levels were significantly increased than in the control group (P0.001). Factor VIII related antigen was slightly elevated, but not statistically significant. Antithrombin activity was significantly decreased (P0.001). The possibility of acute myocardial infarction and thromboembolic diseases are discussed and measures for prevention suggested.