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Among the failure modes of high-grade steel pipelines, cracking or leakage failures of girth welds account for nearly 1/3 in total. Thus, different assessment methods are adopted for various types of indicators, and a risk assessment method based on comprehensive fuzzy theory and index method was proposed. Specifically, the non-quantifiable assessment indicators were obtained by the fault tree method and the maximum membership degree was calculated by combining the fuzzy assessment and the entropy weight method. On this basis, the quantifiable assessment indicators were determined according to the requirements of relevant standards, and their risk values were calculated by the index method. Finally, a risk assessment matrix was established according to the maximum membership degree and risk values obtained with the index method, so as to determine the risk level of girth welds. Herein, risk assessment was performed for the girth welds in a section of Myanmar-China Natural Gas Pipeline with the proposed method. According to the results, the failure risk of girth welds in the pipeline section is mainly determined by the non-quantifiable indicators and the pipeline section is at high risk. Definitely, poor implementation of pipeline maintenance plan, unacceptable qualification of welders, unclear welding procedure specification and other objective factors are the main causes of girth weld failure, and the assessment results are consistent with the field accident reports. Generally, the proposed method supplements and improves the risk assessment system for girth welds of high-grade steel pipelines, and could provide theoretical reference for solving the problem of girth weld failure in high-grade steel pipelines.

Objective To establish a mouse model of acute pseudomembranous stomatitis and to observe the effect of photoactivated disinfection (PAD) on the removal of Candida albicans in vivo, and initially explore the feasibility of this technology in the treatment of acute pseudomembranous stomatitis. Methods Six-week-old male ICR mice were selected and immunized with 1 × 107CFU/mL Candida albicans solution on the backs of the tongues of immunosuppressed mice. Thirty model mice with acute pseudomembranous stomatitis were successfully established and randomly divided into a control group and a photoactivated disinfection group, with 15 mice in each group. Mice in the photoactivated disinfection group were coated with 1 mg/mL toluidine blue solution on the back of the tongue, incubated for 1 min and irradiated with 750 mW LED red light for 1 min. Immediately after treatment, the tongue fungal load was measured in the photoactivated disinfection group and the control group. Tongue fungal load was measured again 48 h later, and tongue histopathological examination was performed in both groups. Results Forty-eight hours after PAD treatment, the white pseudomembrane on the back of the tongue in the photoactivated group was significantly less than the control group. The fungal load on the dorsum of the tongue in the treatment group was significantly lower than the control group immediately and 48 h after treatment for PAD, and the difference was statistically significant (P

The oxidation behavior of GH2984 alloy in pure steam at 750℃ and 850℃ was investigated by using X-ray diffractometer (XRD) and scanning electron microscope equipped with energy dispersive spectra (SEM/EDS). Results show that GH2984 alloy is oxidized parabolically with time. The temperature rising greatly promotes the external and internal oxidation and also the evaporation of Cr. The composition and microstructure of the oxide films change obviously. At 750℃, a compact and single-layered (Cr,Mn)2O3 film is formed on alloy surface; the number of voids in oxide scale increases at 850℃, whereas a three-layered oxide scale consisting of thin Fe2TiO5 outer layer and much thicker (Cr,Mn)2O3 middle layer and thinner (Nb,Mo)2O5 inner layer is formed at the elevated temperature. Ti and Al are internally oxidized preferentially along grain boundaries to be TiO2 and Al2O3, respectively; both the number and the size of the two internal oxides increase with the temperature rising.

Unstressed exposure tests of Inconel 740H alloy tube were carried out at 750℃ for 500-3000h. The microstructure evolution and microhardness were studied by means of thermodynamic simulation, OM, FEG-SEM and microhardness testing. The results show that the tube is qualified if both chemical composition and tensile properties of the as-received alloy meet the corresponding requirements of ASME. After long term exposure, the main precipitates are γ' and M23C6, and no η and σ phase. With the prolonging of exposure time, the coarsening of γ' becomes faster and the law of relationship between the radius of γ' and time accords with LSW Ostwald ripening law; meanwhile, the change in size of M23C6 is not so obvious. During the whole process, microhardness increases firstly and then decreases, but the fluctuation is slight. The changes of microstructure and hardness indicate that, after long time exposure, the domestic Inconel 740H has good stability and can be used for further carrying out the investigation on the mechanical property of creep-rupture.

Objective: To investigate the clinical significance of specific/non-specific neuro-reactive autoantibodies in the pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE)., Methods: Samples of serum and cerebrospinal fluid (CSF) were collected from 25 NPSLE patients, 11 patients with SLE complicated with central nervous system (CNS) infection (control group 1), and 10 SLE patients without CNS infection (non-NPSLE, control group 2)) were detected, Indirect immunofluorescence technique was used to detect the anti-nuclear antibody (ANA) based on the slides with human epithelium cell of laryngocarcinoma of the line Hep-2 or on the slides with cerebellum and peripheral nerve of monkey, he type of immunofluorescence were assayed., Results: The percentages of ANA positive serum of the NPSLE, SLE control 1, and SLE control 2 groups were 92% (23/25), 100% (11/11), and 100% (10/10) respectively without significant differences between any 2 groups (all P > 0.05). The percentage of ANA positive CSF of the NPSLE was 60% (15/25), significantly higher than that of the SLE control group 1 (27%, 3/11, P < 0.01). There was no significant correlation between the titer of serum ANA and the titer of CSF ANA (P > 0.05). The positive rate of neuro-reactive autoantibodies was 40% (10/25), significantly higher than those of the 2 control groups (both 0, both P > 0.001)., Conclusion: (1) The ANA positivity in the CSF of the NPSLE group is associated with the disease activity and CNS involvement, the higher the titer of autoantibodies the severe the clinical manifestations. (2) The neuro-reactive autoantibodies in the serum may associate with NPSLE with still unknown mechanism.

Objective: To observe whether single nucleotide polymorphisms (SNPs) within the OLF1/EBF-associated zinc finger protein (OAZ) gene are associated with lupus nephritis (LN) susceptibility in Chinese population., Methods: Eight SNPs located around the positive microsatellite marker D16S517 within OAZ gene with relatively high heterozygosity were chosen for genotyping on 184 systemic lupus erythromatosus (SLE) patients, including 101 non-LN patients and 83 LN patients, and 286 normal controls using TaqMan MGB allelic discrimination method. Data were collected by SDS 2.0 software. Haplotypes and their frequencies were constructed and estimated, and linkage disequilibrium analysis between pairs of SNPs was evaluated by calculating the D Prime using Helixtree program. Case-control study was performed between the SLE, LN, and non-LN groups and normal control group., Results: (1) The frequency of SNP rs1344531 T allele was 47.0% in the SLE patients, significantly higher than that in the controls [38.1%,; chi(2) = 7.300, P = 0.008, OR (95% CI) = 1.441 (1.105 - 1.878)], which showed that the frequency of SNP rs1344531 T allele is associated with SLE susceptibility. The genotypic distribution of SNP rs1344531(CC/CT/TT) differed significantly between the SLE patients (25.5%/54.9%/19.6%) and normal controls (38.1%/47.6%/14.3%) (chi(2) = 8.394, P = 0.015). The CC genotype frequency of the SLE patients was 25.5%, significantly lower than that of the normal controls [38.1%; chi(2) = 7.976, P = 0.005, OR (95% CI) = 0.557 (0.370 - 0.838)] (2) The SNP rs1344531 T allele frequency of the SLE patients was 53.0%, significantly higher than that of the normal controls [38.1%; chi(2) = 11.769, P = 0.001, OR (95% CI) = 1.832 (1.293 - 2.596)], which showed an associated between SNP rs1344531 T allele frequency and LN susceptibility. The genotypic distribution of SNP rs1344531 (CC/CT/TT) differed significantly between the LN patients (22.9%/48.2%/28.9%) and the normal controls (38.1%/47.6%/14.3%) (chi(2) = 12.065, P = 0.002). The CC genotype frequency of the LN patients was 22.9%, significantly lower than that of the normal controls (38.1%) [chi(2) = 6.578, P = 0.013, OR (95% CI) = 0.481 (0.274 - 0.848)]. The TT genotype frequency of the LN patients was 28.9%, significantly higher than that of the normal controls (14.3%) [chi(2) = 9.423, P = 0.003, OR (95% CI) = 2.431 (1.363 - 4.334)]. No statistical significance was observed between the non-LN patients and normal controls in TT genotype frequency. (3) The frequencies of haplotypes containing rs1344531:rs1420676-rs1344531(C-T) [chi(2) = 11.731, P = 0.001, OR (95% CI) = 1.867 (1.302 - 2.676)], rs3803665-rs1420676-rs1344531(C-C-T) [chi(2) = 8.876, P = 0.004, OR (95% CI) = 1.772 (1.213 - 2.589)], and rs2292155-rs3803665-rs1420676-rs1344531(C-C-C-T) [chi(2) = 9.962, P = 0.002, OR (95% CI) = 1.915 (1.274 - 2.880)] were all significantly higher in the LN patients in comparison with the normal control group (41.0% versus 27.1%; 33.3% versus 21.8%; and 27.0% versus 16.2%); while the frequencies of other haplotypes: rs1344531-rs2080353(C-A) [chi(2) = 8.06, P = 0.005, OR (95% CI) = 0.603 (0.424 - 0.856)], rs1344531-rs2080353-rs933564 (C-A-G) [chi(2) = 7.929, P = 0.006, OR (95% CI) = 0.602 (0.422 - 0.859)] were significantly lower than those of the normal control group (39.5% versus 52.2%, and 36.6% versus 49.2%), which produced additional support for such association., Conclusion: SNP rs1344531 and some haplotypes containing SNP rs1344531 within OAZ are significantly associated with LN susceptibility. Genetic variants of the OAZ gene are involved in the pathogenesis of LN.

Objective: To investigate the expression levels of lymphocyte antigen 6 complex, locus E (LY6E) and interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) genes in the peripheral blood mononuclear cells (PBMCs) of patients with systemic lupus erythematosus (SLE), and to evaluate the relations between these gene expression levels and disease activity., Methods: The clinical data of 144 SLE patients, 27 non-SLE patients with rheumatic diseases, and 59 normal controls were collected. The SLE patients were further divided into 2 subgroups: active SLE group (n = 87) and non-active SLE group (n = 57) according to SLEDAI scores. Specimens of peripheral blood were drawn; total RNA was extracted and transcribed into cDNA. Sybr green dye based real-time quantitative PCR method was used to compare the expression levels (indicated as-DeltaDeltaCT value) of LY6E and IFIT1 in patients with SLE and those in the controls., Results: (1) The-DeltaDeltaCT value of LY6E expression level of the SLE patients was 5.4760 +/- 1.9806, significantly higher than those of the non-SLE patients (3.4323 +/- 1.7456) and normal controls (4.5198 +/- 1.6359, both P = 0.001). (2) The-DeltaDeltaCT value of LY6E and IFIT1 mRNA expression of the active SLE patients were 6.1960 +/- 1.7729 and 6.4997 +/- 2.6297 respectively, significantly higher than those observed in the inactive SLE patients (4.3770 +/- 1.7764 and 4.1327 +/- 2.6044 respectively, both P = 0.000). The-DeltaDeltaCT values of LY6E and IFIT1 mRNA of the SLE patients were correlated with the SLEDAI scores, and with the numbers of matched criteria used in the diagnosis of SLE (P < 0.001)., Conclusion: As IFN-induced genes, elevated expression of LY6E mRNA is specific to diagnosis of SLE. The real time expression levels of LY6E and IFIT1 genes are associated with SLE disease activity. To inhibit the expression of LY6E and IFIT1 may become a novel therapeutic approach for SLE.

Objective: To investigate the protein-to-protein interaction of interferon-induced protein with tetratricopeptide repeats 1 (IFIT1), a newly discovered systemic lupus erythematosus (SLE) related up-regulated gene, and its possible function., Methods: Peripheral blood of 40 SLE patients was obtained to extract total RNA and synthesized cDNA. Real-time PCR was used to determine the IFIT1 expression at transcript level. Peripheral blood of another 10 SLE patients was extracted to obtain specimens of white blood cell lysate. Molecular cloning and a modified gluthion S-transferase (GST)-pull down assay were used to capture the protein interacting with IFIT1 in the specimens of white blood cell lysate. MALDI-TOF mass spectrometry (MS) was preformed to identify the captured protein that could interact with IFIT1. Twenty-nine sex and age-matched healthy persons were used as controls., Results: By real-time PCR showed that the IFIT1Delta Ct value (x +/- s) was 2.344 +/- 1.200 in the SLE patients and was 3.734 +/- 1.274 in the controls (P < 0.001), showing a significant up-regulation in SLE patients. IFIT1 was cloned and GST-IFIT1 fusion protein was expressed in Escherichia coli. GST-IFIT1 fusion protein was further purified using Glutathione Sepharose 4B column, and was treated as bait to capture prey from peripheral white blood cell lysate of SLE patients. MALDI-TOF MS detected protein interaction between Rho/Rac guanine nucleotide exchange factor and IFIT1., Conclusion: IFIT1 may interact with Rho/Rac guanine nucleotide exchange factor, and regulate the activation of Rho/Rac proteins, thus being involved in the pathogenesis of SLE.