Diagnostic value of transbronchial lung biopsy in peripheral lung cancer

Objective: The purpose of this study was to evaluate the diagnostic value of transbronchial lung biopsy (TBLB) in peripheral lung cancer. Methods: 78 cases of peripheral lung cancer which could not be observed by bronchoscope were selected from the Second Affiliated Hospital of Sun Yat-sen University (China), of which 42 cases were diagnosed by TBLB. Among the 36 cases of peripheral lung cancer that could not be able to be diagnosed by TBLB, 22 cases were diagnosed by percutaneous lung biopsy (PNLB) and 14 cases being left were diagnosed by surgical specimens biopsy, lymphadenopathy biopsy, pleural biopsy or pleural effusion cytology. Results: The positive rates produced by TBLB and transbronchial brush biopsy were 53.8% and 8.9%, respectively, and the combined positive rate was 57.7%. The positive rate produced by TBLB was higher than that of transbronchial brush biopsy (P < 0.01). As the tumor’s diameter increased, the positive rate of the biopsy was higher (P < 0.05). The positive rate of biopsy of the right lung was not significantly higher than that of the left lung (P > 0.05). The positive rate of biopsy of the inferior lobes was not significantly higher than that of the upper lobes of the lung (P > 0.05). The lesions of the tumors which were nearer to the infield and hilar of the lung got a higher positive rate (P < 0.01). The incidence of complications in PNLB was much higher than that in TBLB (P < 0.05). Conclusion: TBLB is an important method in the diagnosis of peripheral lung cancer. Combination of TBLB and other methods can increase the positive rate in the diagnosis of peripheral lung cancer.

Characteristics of Polyimide Debris Clouds Produced by Hypervelocity Impact

Polyimide is a typical complex high-molecular polymer of imide monomers,which is widely used in the manufacture of parts for aerospace engineering.The hypervelocity impacts between the spacecraft and orbital debris can induce great damage to the spacecraft.In order to improve the safety of spacecraft,the characteristics of polyimide debris clouds produced by hypervelocity impact should be studied.Firstly,a Mie-Grüneisen equation of state based on the shock adiabat for polyimide,which describes the mechanical behavior in the numerical simulation,was obtained from hypervelocity impact experiments,then a 3-dimentional smoothed particle hydrodynamics program was compiled to numerically simulate the hypervelocity impact between aluminum projectiles(orbital debris)and polyimide targets with different impact velocities(3.km/s,5.km/s,8.km/s)and angles(0°,30°,45°,60°),finally typical shapes of debris clouds produced in different impact velocities and angles were collected from simulation results,the characteristics of which were systemically discussed.

Research on the Constitutive Behavior of the Sintered Reactive Material PTFE/Al/Si

The constitutive behaviors of the sintered reactive material PTFE/Al/Si, one new formulation proposed by the author, were studied systematically and found it appears strain-harden, stain-rate harden and temperature-soften effects, so it is more appropriate to describe the mechanical behavior with the Johnson-Cook model. With the static and dynamic experimental results and using the nonlinear fitting method, the mechanical and physical parameters in the Johnson-Cook model were determined, which supply one basis for the future numerical simulation study.