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Take a certain engineering vehicle as an example, use the application of the finite element analysis method, establish the finite element of the vehicle and passenger compartment cavity model, comparative stiffness calculation results, and test results verify the accuracy of the model. Focuses on the application of modal analysis method and acoustic mode, establish the acoustic-structural coupled finite element model, calculating modal participation factors, and the plate body structure contribution, structure analysis of sensitivity, noise source identification of main vehicle. The main noise source to take corresponding improvement measures, can effectively restrain the noise, to verify the correctness of the analysis method.

To identify susceptibility variants for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), we conducted a genome-wide association study by genotyping 440,794 SNPs in 355 chronic HBV carriers with HCC and 360 chronic HBV carriers without HCC, all of Chinese ancestry. We identified one intronic SNP (rs17401966) in KIF1B on chromosome 1p36.22 that was highly associated with HBV-related HCC and confirmed this association in five additional independent samples, consisting of 1,962 individuals with HCC, 1,430 control subjects and 159 family trios. Across the six studies, the association with rs17401966 was highly statistically significant (joint odds ratio = 0.61, P = 1.7 x 10(-18)). In addition to KIF1B, the association region tagged two other plausible causative genes, UBE4B and PGD. Our findings provide evidence that the 1p36.22 locus confers susceptibility to HBV-related HCC, and suggest that KIF1B-, UBE4B- or PGD-related pathways might be involved in the pathogenesis of this malignancy.

Modulation of urinary excretion of green tea polyphenols (GTPs) and oxidative DNA damage biomarker, 8-hydroxydeoxyguanosine (8-OHdG), were assessed in urine samples collected from a randomized, double-blinded and placebo-controlled phase IIa chemoprevention trial with GTP in 124 individuals. These individuals were sero-positive for both HBsAg and aflatoxin-albumin adducts, and took GTP capsules daily at doses of 500 mg, 1000 mg or a placebo for 3 months. Twenty-four hour urine samples were collected before the intervention and at the first and third month of the study. Urinary excretion of 8-OHdG and GTP components was measured by HPLC-CoulArray electrochemical detection. The baseline levels of 8-OHdG and GTP components among the three groups showed homogeneity (P > 0.70), and a non-significant fluctuation was observed in the placebo group over the 3 months (P > 0.30). In GTP-treated groups, epigallocatechin (EGC) and epicatechin (EC) levels displayed significant and dose-dependent increases in both the 500 mg group and 1000 mg group (P < 0.05). The 8-OHdG levels did not differ between the three groups at the 1 month collection, with medians of 1.83, 2.08 and 1.86 ng/mg-creatinine for placebo, 500 and 1000 mg group, respectively (P = 0.999). At the end of the 3 months' intervention, 8-OHdG levels decreased significantly in both GTP-treated groups, with medians of 2.02, 1.03 and 1.15 ng/mg-creatinine for placebo, 500 mg and 1000 mg group, respectively (P = 0.007). These results suggest that urinary excretions of EGC and EC can serve as practical biomarkers for green tea consumption in human populations. The results also suggest that chemoprevention with GTP is effective in diminishing oxidative DNA damage.

A certain engineering vehicle is taken as an example to build up the three-dimensional and full-floating cab 3D model and establish the vibration response model in the Adams platform. The vibration decoupling theory is applied to optimize the vibration stiffness of suspension and arrangement angle. The basic vibration isolation theory is used in the frequency domain for the analysis and calculation of transmission. Optimization results of the suspension system are verified, and the cab suspension system dynamics model of vehicle is created on the RecurDyn platform. The cab suspension system is placed in the vehicle for the comfort simulation to improve the comfort of the driver. NVH performance is improved with satisfactory results.

OBJECTIVES Aflatoxin B1 exposure is one of the major risk factors for hepatocellular carcinoma (HCC). CYP1A2 is a cytochrome P450 isoenzyme that plays an important role in the bioactivation of AFB1 to its carcinogenic metabolite. The study was designed to assess whether genetic polymorphisms in CYP1A2 are associated with HCC susceptibility in a high-risk region. METHODS A case-control study of 431 HCC cases and 550 cancer-free controls recruited from an HCC endemic region in China was carried out. Three single nucleotide polymorphisms, namely -3860G > A (CYP1A2*1C), -3113G > A, and 5347T > C (CYP1A2*1B) were genotyped by polymerase chain reaction-restriction fragment length polymorphism methods. RESULTS Homozygous carriers of the major haplotype -3860G/-3113G/5347C were associated with increased HCC susceptibility in the overall population (odds ratio [OR] = 1.65, 95% confidence interval [CI]: 1.11-2.46, P = 0.014), in HBsAg seronegative individuals (OR = 2.69, 95% CI: 1.43-5.06, P = 0.002), and in heavy smokers (OR = 2.14, 95% CI: 1.21-3.80, P=0.009). In addition, individuals carrying at least one CYP1A2*1C allele showed significantly decreased HCC risk (OR = 0.49, 95% CI: Q0.27-0.86, P = 0.013) in the HBsAg seronegative subpopulation. Furthermore, as compared with HBsAg seropositive patients, wild-type homozygotes of the CYP1A2*1C polymorphism were significantly over-represented in HBsAg seronegative patients (P = 0.024). No significant association between CYP1A2 genetic polymorphisms and HCC risk was observed in either HBsAg seropositive individuals or non-smokers. CONCLUSIONS CYP1A2 genetic polymorphisms are associated with HCC susceptibility in smokers and HBsAg seronegative individuals in the Fusui endemic region.