精氨酸甲基转移酶(PRMT)7通过IGF-1信号通路调控人骨髓间充质干细胞成脂分化的研究

目的本研究旨在明确精氨酸甲基转移酶(PRMT)7在人骨髓间充质干细胞(hBMSCs)成脂分化过程中的变化以及是否调控hBMSCs成脂分化,进而探索相应的调控机制。方法通过定量反转录PCR(qRT-PCR)和蛋白质印迹(Western blot)检测hBMSCs成脂分化过程中PRMT7的变化;通过qRT-PCR和Western blot实验证明PRMT7稳定敲低细胞系构建成功。进行油红O染色和定量分析,以及qRT-PCR和Western blot实验检测PRMT7稳定敲低细胞系成脂分化水平的变化;通过裸鼠体内异位成脂实验,油红O染色检测PRMT7稳定敲低细胞系体内异位成脂的效果;通过qRT-PCR和Western blot证明PRMT7稳定过表达细胞系构建成功。进行油红O染色和定量分析以及qRT-PCR和Western blot实验检测PRMT7稳定过表达细胞系成脂分化水平的变化;通过q RT-PCR和Western blot实验检测敲低PRMT7和过表达PRMT7的细胞中IGF-1表达水平的变化。在PRMT7稳定敲低细胞系中转染siIGF-1并通过qRT-PCR和Western blot检测IGF-1的表达水平验证敲低效率。通过油红O染色和定量分析,qRT-PCR实验检测转染siIGF-1的敲低组hBMSCs成脂分化水平的变化。结果本文发现:在hBMSCs成脂过程中,PRMT7表达水平明显降低(P<0.01);敲低PRMT7后hBMSCs的成脂分化能力增强(P<0.001);敲低PRMT7后hBMSCs的体内异位成脂分化能力增强;过表达PRMT7后hBMSCs的成脂分化能力减弱(P<0.01);PRMT7敲低后IGF-1表达水平增加(P<0.0001);PRMT7过表达后IGF-1表达水平降低(P<0.0001);转染siIGF-1后,各细胞系IGF-1表达水平明显降低(P<0.001);敲低组转染siIGF-1后成脂分化能力明显降低(P<0.01)。结论本研究通过细胞水平和裸鼠皮下移植实验发现PRMT7显著抑制hBMSCs成脂分化,机制研究发现PRMT7对hBMSCs成脂分化的调控作用依赖IGF-1信号通路。上述研究表明,PRMT7可能是治疗相关疾病的潜在分子靶点,为PRMT7和hBMSCs应用于相关疾病治疗提供了新思路。

Effects of Fujian tablet on Nogo-A mRNA expression and plasticity of the corticospinal tract in a rat model of focal cerebral ischemia

The present study investigated the effects of Fujian tablet, a Chinese medicine compound that can nourish liver and kidney, on corticospinal tract plasticity and cervical cord microenvironment in rats with focal cerebral ischemia. Results showed that motor function of rats with right proximal middle cerebral artery occlusion was significantly improved following treatment with Fujian tablet, 9 g crude drug/kg. Anterograde tracing revealed significantly increased biotinylated dextran amine expression in the denervated （left） side of the cervical cord （C4-6） following Fujian tablet treatment, and significantly decreased Nogo-A mRNA expression was detected in the denervated side of the cervical cord （C4-6） using in situ hybridization. Pearson＇s correlation analysis showed a negative correlation between biotinylated dextran amine and Nogo-A mRNA expression （r = -0.943, P 〈 0.01）. Results demonstrated that Fujian tablet can promote corticospinal tract plasticity possibly through the inhibitory effect on Nogo-A mRNA expression in the cervical spinal cord, thereby improving motor dysfunction.

Suppressing stimulated Raman side-scattering with vector light

Recent observations of stimulated Raman side-scattering(SRSS)in different laser inertial confinement fusion ignition schemes have revealed that there is an underlying risk of SRSS on ignition.In this paper,we propose a method that uses the nonuniform nature of the polarization of vector light to suppress SRSS,and we give an additional threshold condition determined by the parameters of the vector light.For SRSS at 90°,where the scattered electromagnetic wave travels perpendicular to the density profile,the variation in polarization of the pump will change the wave vector of the scattered light,thereby reducing the growth length and preventing the scattered electromagnetic wave from growing.This suppression scheme is verified through three-dimensional particle-in-cell simulations.Our illustrative simulation results demonstrate that for linearly polarized Gaussian light,there is a strong SRSS signal in the 90°direction,whereas for vector light,there is very little SRSS signal,even when the conditions significantly exceed the threshold for SRSS.We also discuss the impact of vector light on stimulated Raman backscattering,collective stimulated Brillouin scattering and two-plasmon decay.

Designing a risk prognosis model based on natural killer cell-linked genes to accurately evaluate the prognosis of gastric cancer

Background:This study was aimed at identifying natural killer(NK)cell-related genes to design a risk prognosis model for the accurate evaluation of gastric cancer(GC)prognosis.Methods:We obtained NK cell-related genes from various databases,followed by Cox regression analysis and molecular typing to identify prognostic genes.Various immune algorithms and enrichment analyses were used to investigate the mutations,immune status,and pathway variations among different genotypes.The key prognostic genes were assessed using the least absolute shrinkage and selection operator(Lasso)regression analysis and univariate Cox regression analysis.Thereafter,the risk score(RS)prognosis model was constructed based on the selected important prognostic genes.A Receiver Operating Characteristics(ROC)curve was plotted for analyzing the robustness of the model.Subsequently,the decision and calibration curves were used for assessing the reliability and prediction accuracy of the proposed model.The‘pRRophetic’R software package was utilized for predicting the half-maximal inhibitory concentration(IC50)of immunotherapy and chemotherapy drugs.Results:We screened 21 prognostic genes and three molecular subtypes and found that the C1 subtype had the worst prognosis.Further,the pathways promoting tumor proliferation,such as epithelial-mesenchymal transition were significantly up-regulated.The results also showed that the macrophages in the M2 stage were significantly infiltrated in the C1 subtype,and there was significant overexpression in the C1 subtype,accompanied by a severe inflammatory reaction.The C1 was highly sensitive to drugs like 5-fluorouracil and paclitaxel.The ROC,calibration curve,and decision curve showed that the risk model was robust and strongly reliable.Conclusion:Overall,our proposed NK cell-related RS model can be used as a more accurate prediction index for GC patients,providing a valuable contribution to personalized medicine.

Inverse Faraday effect of weakly relativistic full Poincaré beams in plasma

The inverse Faraday effect(IFE),which usually refers to the phenomenon in which a quasi-static axial magnetic field is self-generated when a circularly polarized beam propagates in a plasma,has rarely been studied for lasers with unconventional polarization states.In this paper,IFE is reconsidered for weakly relativistic full Poincarébeams,which can contain all possible laser polarization states.Starting from cold electron fluid equations and the conservation of generalized vorticity,a self-consistent theoretical model combining the nonlinear azimuthal current and diamagnetic current is presented.The theoretical results show that when such a laser propagates in a plasma,an azimuthally varying quasi-static axial magnetic field can be generated,which is quite different from the circularly polarized case.These results are qualitatively and quantitatively verified by three-dimensional particle-in-cell simulations.Our work extends the theoretical understanding of the IFE and provides a new degree of freedom in the design of magnetized plasma devices.

晶、胶体容量预负荷降低蛛网膜下隙阻滞剖宫产术中低血压发生率的Meta分析

目的蛛网膜下隙阻滞下行剖宫产术,麻醉前10~30 min或麻醉同时预先输注一定容量的晶、胶体溶液可有效减少术中低血压及恶心、呕吐的发生率,但对补充晶体液或胶体液、补液量以及补液时机的选择目前仍存争议。该文采用Meta分析的方法进行系统评价,为临床补液策略提供参考。方法选择PubMed、EMBASE、Cochrane Library及Research Gate数据库,检索所有相关随机对照试验。主要指标为术中出现低血压患者的数量;次要指标为术中出现恶心、呕吐症状患者的数量。结局各指标均采用随机效应模型,用比值比(O^R)及95%可信区间(95%CI)进行表示。结果蛛网膜下隙阻滞下行剖宫产术,与晶体液相比,同等量胶体预负荷可使术中低血压发生率降低[O^R=0.40(95%CI:0.27,0.59)];麻醉前10~30 min或麻醉同时快速输注500 ml胶体液可使术中低血压发生率降低[O^R=0.45(95%CI:0.31,0.66)],同等量晶、胶体容量预负荷在降低术中恶心、呕吐方面则无明显差异,均可使术中恶心、呕吐几率降低[O^R=0.72(95%CI:0.43,1.19)]。结论蛛网膜下隙阻滞下行剖宫产术,麻醉前10~30 min或麻醉同时预先快速输注500 ml胶体溶液可显著降低产妇术中低血压的发生率。

Distributions of crystals and gas bubbles in reservoir ice during growth period

In order to understand the dominant factors of the physical properties of ice in ice thermodynamics and mechanics, in-situ observations of ice growth and decay processes were carried out. Two samplings were conducted in the fast and steady ice growth stages. Ice pieces were used to observe ice crystals and gas bubbles in ice, and to measure the ice density. Vertical profiles of the type and size of ice crystals, shape and size of gas bubbles, and gas bubble content, as well as the ice density, were obtained. The results show that the upper layer of the ice pieces is granular ice and the lower layer is columnar ice; the average crystal size increases with the ice depth and remains steady in the fast and steady ice growth stages; the shape of gas bubbles in the upper layer of ice pieces is spherical with higher total content, and the shape in the middle and lower layers is cylinder with lower total content; the gas bubble size and content vary with the ice growth stage; and the ice density decreases with the increase of the gas bubble content.

High performance n^+p-Si/Ti/NiS_xO_y photocathode for photoelectrochemical hydrogen evolution in alkaline solution

Silicon, as a promising semiconductor for fabricating photocathode toward photoelectrochemical hydrogen evolution reaction(PEC-HER), should be improved in light harvesting ability and catalytic kinetics to obtain high PEC performance. Herein, a novel amorphous Nickel Oxysulfide(NiS_xO_y) film is effectively integrated with a Ti protected n^+p-Si micropyramid photocathode by the electrodeposition method. The fabricated n^+p-Si/Ti/Ni SxOyphotocathode exhibits excellent PEC-HER performance with an onset potential of 0.5 V(at J =-0.1 mA/cm^2), a photocurrent density of-26 mA/cm^2 at 0 V vs. RHE, and long term stability of six hours in alkaline solution(pH ≈ 14). The synergy of unique n^+p-Si micropyramid architectures(omnidirectional broadband light harvesting ability), novel amorphous NiS_xO_y catalyst(high HER electrocatalytic activity and good optical transparency) results in the high performance of n^+pSi/Ti/Ni S_xO_y. This work offers a novel strategy for effectively integrating electrocatalysts with semiconductor to design efficient photoelectrode toward PEC water splitting.

Cloning and sequence analysis of nine novel MYB genes in Taxodiaceae plants

Myeloblastosis （MYB） is one of the largest transcribed factor families in plants. To gain an overall picture of the evolution of MYB genes in relict plants, we cloned nine novel MYB genes in Taxodiaceae plants （ Taxodium distichum, Taxodium ascendens, Cryptomeria japonica var. Sinensis, Cryptomeria japonica cv. Araucarioides, Cryptomer Ja- ponica, Metasequoia glyptostroboides, Cunninghamia lanceolata, Tai- wania cryptomerioides and Glyptostrobus pensilis）. The deduced amino acid sequences for MYBs showed that the nine MYB proteins contained two DNA binding domains. The first domain is from amino acid position 29 to 78, wherein three tryptophanes at 33, 53 and 73 were separated by 19 amino acids, respectively. The second domain is from amino acid position 82 to 127, wherein three tryptophanes at 86, 105 and 124 were separated by 18 amino acids, respectively, whereas the first tryptophane at amino acid position 86 is replaced by a phenylalanine. The characteri- zation of these conserved domains at nine MYBs indicated that they all belong to the R2R3-MYB group. The secondary structure analysis showed that a-helix and 13-turn are the major motifs of the predicted secondary structure of MYBs. The three dimensional model of each MYB protein showed that the structure is like clip, making it more flexi- ble and mobile. The similarities between the nine MYB proteins in Taxodiaceae were calculated. The highest identical value of 99% is be- tween CjsMYB, CjMYB and CjaMYB, whereas the lowest value of 82% is between TaMYB and C1MYB. According to the phylogenetic tree, the distances between different genera were relatively large whereas those within genera were relatively small. As expected, accessions of the same genus formed a subgroup before being grouped with other genera.

DNA methylation in tissues of Chamaedorea elegans

DNA methylation plays a crucial role in regulating plant development and tissue differentiation. In this study, we compared the methylation levels in leaf, root, and stem in Chamaedorea elegans by using the technique of methylation-sensitive amplified fragment length polymorphism AFLP. Over 19% （42/220） bases were uniformly methy- lated in these tissues. The percentages of polymorphism resulting from varied methylation in mature leaf （L1）, young leaf （L2）, baby leaf （L3）, stem （S）, young root （R1） and lignified root （R2） were 29.5%, 29.0%, 27.1%, 30.7%, 63.0% and 28.3%, respectively. The numbers of poly- morphic loci detected in the leaves of three developmental stages were similar, ranging from 20 to 30. In contrast, roots at the two developmental stages differed greatly, with 145 polymorphic loci detected in R1 and 27 in R2. Our results suggest that the methylation level in leaves slightly increases with aging, while that in roots decreases dramatically with aging.

Wear-resistant Ag-MAX phase 3D interpenetrating-phase composites:Processing,structure,and properties

Electrical contact materials are generally Ag-or Cu-based composites and play a critical role in ensuring the reliability and efficiency of electrical equipments and electronic instruments.The MAX(M is an early transition metal,A is an element from III or IV main groups,and X is carbon or/and nitrogen)phase ceramics display a unique combination of properties and may serve as an ideal reinforcement phase for electrical contact materials.The biological materials evolved in nature generally exhibit three-dimensional(3D)interpenetrating-phase architectures,which may offer useful inspiration for the architectural design of electrical contact materials.Here,a series of bi-continuous Ag-Ti_(3)SiC_(2) MAX phase composites with high ceramic contents exceeding 50 vol.%and having micron-and ultrafine-scaled 3D interpenetrating-phase architectures,wherein both constituents were continuous and mutually interspersed,were exploited by pressureless infiltration of Ag melt into partially sintered Ti_(3)SiC_(2) scaffolds.The mechanical and electrical properties as well as the friction and wear performance of the composites were investigated and revealed to be closely dependent on the ceramic contents and characteristic structural dimensions.The composites exhibited a good combination of properties with high hardness over 2.3 GPa,high flexural strength exceeding 530 MPa,decent fracture toughness over 10 MPa·m^(1/2),and good wear resistance with low wear rate at an order of 10^(-5)mm^(3)/(N·m),which were much superior compared to the counterparts made by powder metallurgy methods.In particular,the hardness,electrical conductivity,strength,and fracture toughness of the composites demonstrated a simultaneous improvement as the structure was refined from micron-to ultrafine-scales at equivalent ceramic contents.The good combination of properties along with the facile processing route makes the Ag-Ti_(3)SiC_(2)3D interpenetrating-phase composites appealing for electrical contact applications.

Laser pulse shape designer for direct-drive inertial confinement fusion implosions

Pulse shaping is a powerful tool for mitigating implosion instabilities in direct-drive inertial confinement fusion(ICF).However,the high-dimensional and nonlinear nature of implosions makes the pulse optimization quite challenging.In this research,we develop a machine-learning pulse shape designer to achieve high compression density and stable implosion.The facility-specific laser imprint pattern is considered in the optimization,which makes the pulse design more relevant.The designer is applied to the novel double-cone ignition scheme,and simulation shows that the optimized pulse increases the areal density expectation by 16%in one dimension,and the clean-fuel thickness by a factor of four in two dimensions.This pulse shape designer could be a useful tool for direct-drive ICF instability control.

Influence of Hot-Rolling Deformation on Microstructure,Crystalline Orientation,and Texture Evolution of the Ti6Al4V-5Cu Alloy

The influence of hot-deformation on the microstructure,crystalline orientation,and texture evolution of Ti6Al4V-5Cu,an antibacterial(α+β)titanium alloy,was investigated.The alloy was deformed using a hot rolling process in 15%,58%,and 73%thickness reduction ratios.It was found that the basal<α→>and pyramidal<c→+α→>type slip planes could be activated in theαphase,which dominated the deformation behavior of Ti6Al4V-5Cu alloy.Under various deformation conditions,the alloy revealed different microstructure features.On the 15%hot rolled alloy,the deformation was performed by the breakdown of priorβgrain boundaries(GBβ),which was attributed to the formation of coarseαgrains,rotated nearly 45°with respect to the transversal and rolling directions.The presence of different sub-structure geometries made the interior grain size distribution heterogeneous.On the 58%hot rolled alloy,Ti2Cu intermetallic compound was found at theα/βinterface.High-resolution transmission electron microscopy investigation showed the occurrence of grain rotation in different crystallographic directions.At room temperature,the percentage elongation(El)of the alloy reached 23.15%on the 58%hot rolled sample.On the 73%deformed alloy,refined and randomly oriented characteristics of grains were obtained due to higher thickness reduction,which resulted from the segregation of very fine granules.The influence of grain rotation during a hot rolling process revealed that theα/βtexture fiber separation angle to maintain the Burger orientation relationship of{0001}α//{110}βplanes decreased with increase of the thickness reduction ratio when Ti6Al4V-5Cu alloy was deformed by a hot rolling mechanism.Activation of tensile{1012}<1011>and compressive{1122}<1123>twins on the deformation of the alloy was also studied.

Fabrication of textured Ti2AlC lamellar composites with improved mechanical properties

Textured Ti2AlC lamellar composites have been successfully fabricated by a new method in the present work.The composites exhibit high compressive strength of ca 2 GPa,fracture toughness of 8.5 MPa m1/2(//c-axis),flexural strength of 735 MPa(//c-axis)and high hardness of 7.9 GPa(//c-axis).The strengthening mechanisms were discussed.The sintering and densification process was investigated and crystal orientation and microstructure were studied by electron backscattered diffraction techniques.The synthesis temperature is reduced to 1200?C by using high surface-to-volume ratio Ti2AlC nano flakes.The Lotgering orientation factor of Ti2 AlC and Ti3 AlC2{00 l}planes in the textured top surface reaches 0.74 and 0.49,respectively.This new route may shed light on resolving the difficulties encountered in large scale fabrication of textured MAX phases.

Silicon lithium-ion battery anode with enhanced performance： Multiple effects of silver nanoparticles

Silicon has been regarded as one of the most promising next generation lithium-ion battery anode. How- ever, the poor cyclic stability of the Si based anode has severely limited its practical applications, which is even worse with high mass loading density （〉1 mg cm^-2 ）. A new concept has been developed to enhance the electrochemical performance of the Si nanoparticle anode. Silver nanoparticles are composited with the silicon nanoparticles in a facile way for the first time. It is found that the mechanical properties of the Si electrode have been significantly improved by the incorporation of the silver nanoparticles, leading to enhanced cyclic performance. With the Si/Ag mass ratio of 4：1, the reversible specific discharge capacity is retained as l 156 mA h g^-1 after 100 cycles at 200 mAg^-1, which is more than three times higher than that of the bare silicon （318 mA h g^-1 ）. The rate performance has been effectively improved as well due to excellent electron conductivity of the silver nanoparticles.

Seeded growth of Ti-46Al-8Nb polysynthetically twinned crystals with an ultra-high elongation

Large size polysynthetically twinned crystals of Ti-46 Al-8 Nb alloy with a parallel lamellar microstructure were successfully prepared using a Ti-43 Al-3 Si seed by our new operation.A large amount of columnar B2 phase paralleling to the growth direction was found in the final lamellar microstructure.Higher growth rate(>30 mm/h)led to the failure of seeding process.Based on these results,a new mechanism is proposed to describe the seeding process of the hypo-peritectic Ti Al alloys.The peritecticαphase is suggested to directly nucleate from the melt,and then act as nucleus for transformedαphase in the subsequentβtoαtransformation.At the higher growth rate,the appearance ofβphase secondary dendrites and homogeneous nucleation lead to the failure of seeding process.High Nb addition leads to a large amount of residualβphase,and theseβdendrites finally evolve into B2 phase.The room temperature tensile elongation was measured to be 11.9-18.5%for Ti-46 Al-8 Nb PST crystals,which is the highest ever reported value for Ti Al based alloys.

Tensile Behavior of SiC Fiber-Reinforcedγ-TiAl Composites Prepared by Suction Casting

The process of preparing SiC_(f)iber-reinforced y-TiAl composites by the conventional methods is difficult and complicated due to the high reactivity,high melting point and poor deformability of y-TiAl alloys.In this work,suction casting,a promising method for preparing SiC_(f)/TiAl composite,had been attempted.In the process,y-TiAl alloy melt was introduced rapidly into a mold within pre-arranged fibers that were coated with additional layer of titanium alloy.This simple method successfully prevented serious reactions between the alloy melt and the fibers which remained intact during the solidification process.The interfacial reaction layer was observed by optical microscopy,scanning electron microscopy(SEM).The interfacial reaction products were identified by transmission electron microscopy(TEM).Tensile tests of the matrix alloy and composites were performed at room temperature and 800℃.The results exhibited that the tensile strength of SiC_(f)/γ-TiAl composite was higher than that of the matrix alloy at both room temperature and 8000 C.At room temperature,tensile strength of SiC_(f)/γ-TiAl composite was increased by about 7%(50 MPa),whereas a double increase in tensile strength 14%(100 MPa)was obtained at 800℃.The titanium alloy coating on the fiber not only prevented the serious interfacial reaction between the y-TiAl alloy melt and the SiC_(f)iber,but also played a role in delaying the propagation of cracks in the matrix to the fiber at 800℃.The fracture mechanism of the composite was analyzed by fracture metallographic analysis.

CuS/RGO hybrid by one-pot hydrothermal method for efficient electrochemical sensing of hydrogen peroxide

In this study,a non-enzymatic hydrogen peroxide sensor was successfully fabricated on the basis of copper sulfide nanoparticles/reduced graphene oxide（CuS/RGO） electrocatalyst.Using thiourea as reducing agent and sulfur donor,CuS/RGO hybrid was synthesized through a facile one-pot hydrothermal method,where the reduction of GO and deposition of CuS nanoparticles on RGO occur simultaneously.The results confirmed that the CuS/RGO hybrid helps to prevent the aggregation of CuS nanoparticles.Electrochemical investigation showed that the as-prepared hydrogen peroxide sensor exhibited a low detection limit of 0.18μmol/L（S/N = 3）,a good reproducibility（relative standard deviation（RSD） of4.21%）,a wide linear range（from 3 to 1215 μmol/L） with a sensitivity of 216.9 μA L/mmol/cm-2 under the optimal conditions.Moreover,the as-prepared sensor also showed excellent selectivity and stability for hydrogen peroxide detection.The excellent performance of CuS/RGO hybrid,especially the lower detection limit than certain enzymes and noble metal nanomaterials ever reported,makes it a promising candidate for non-enzymatic H2O2 sensors.

Fabrication of three dimensional SiC@C hybrid for efficient direct dehydrogenation of ethylbenzene to styrene

Synthesis of hybrid carbon materials with core-shell structure and robust catalytic performance is of great research interest,and remains a great challenge in catalytic dehydrogenation of hydrocarbons reaction.In this paper,few-layer sp^(2) carbon decorated SiC nanocrystals with core-shell structure(SiC@C)were fabricated through a dual-confined magnesiothermic method by employing glucose and SiO_(2) as precursors.The SiC@C nanocrystals were further crosslinked to be a three dimensional(3D)mesoporous hybrid by the in situ generated carbon as binders and exhibiting a 410.30 m^(2) g^(−1) large surface area.The as-prepared SiC@C hybrid materials as metal-free catalysts were evaluated in the steam-free direct dehydrogenation of ethylbenzene to styrene.Benefiting from the abundant surface carbonyl groups on the graphite carbon layers,the optimized yield rate of styrene normalized by carbon mass was as high as 11.58 mmol g^(−1) carbon h^(−1),nearly 4 times that of nanodiamonds.Considering the low cost and excellent catalytic activity,the hybrid 3D SiC@C material may be a promising candidate for direct dehydrogenation of hydrocarbons.

Inhibition effect on microbiologically influenced corrosion of Ti-6Al-4V-5Cu alloy against marine bacterium Pseudomonas aeruginosa

With rapid development of marine infrastructures,materials with better biocorrosion resistance and antibiofouling performance will be highly demanded.Ti6Al4V alloy is susceptible to the above.The inhibition to the microbiologically influenced corrosion of Ti6Al4V-5Cu alloy against Pseudomonas aeruginosa was investigated using antibacterial test,electrochemical techniques,surface analysis,and weight loss test conducted for 2.5 months.At a sputtering depth of 0 nm,the passive film of Ti6Al4V-5Cu alloy was mainly composed of ideal oxide TiO_(2).With increasing sputtering thickness to 6 nm,Ti_(2)O_(3)and TiO were detected with a relative fraction of 14.6%and 14.8%,respectively,in the oxide layer of Ti6Al4V-5Cu alloy.In contrast,the outermost layer of Ti6AlV alloy was predominantly composed of TiO_(2)but Ti_(2)O_(3)(22.8%),Al_(2)O_(3)and V_(2)O_(5) were also detected.With increasing sputtering depth to 6 nm,fitting revealed the presence of Ti_(2)O_(3)and TiO with relative fractions of 25.3%and 35.8%,respectively.Yet,a spot of TiO(8%)was also observed at 12 nm in the oxide layer of Ti6Al4V alloy.Although the addition of Cu into Ti6Al4V alloy generated the self-healing property of passive film in the presence of P.aeruginosa,it also reduced resistance to corrosion in general condition.