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Objective A retrospective study of the clinical and radiological results between local bone graft with a cage and without cage in patients treated with unilateral fixation and posterior lumbar interbody fusion surgery. Methods A total of 52 patients who underwent PLIF in our institution were evaluated from January 2015 to January 2018. 30 of these patients received PLIF with local bone graft combined with using one cage, and 22 patients received PLIF with local bone graft without using cage. The clinical data and perioperative complications of the two groups were recorded. X-ray were taken before, after operation and at the end of follow-up to calculate the height of intervertebral disc and the fusion rate. SUK's criteria were used to evaluate the quality of spinal fusion at the follow-up time. The results between the cage and non- cage group were compared. Results There was no statistical difference in baseline data between the two groups, and The mean follow-up time was 18.43 months in cage group and 17.50 months in non- cage group (P = 0.553). In additions, the significant difference was not found in the comparison of perioperative evaluation data between the two groups, such as operation time (P = 0.299), blood loss (P = 0.342) and incidence of complications (P = 1.000). Furthermore, the significant difference of VAS score cannot be found in preoperation (Pleg=0.731, Plowback=0.786), postoperation (Pleg=0.534, Plowback=0.725) and the final follow-up (Pleg=0.654, Plowback=0.362) between the two groups. The same results were also obtained in the comparison of ODI index (Ppre=0.682, Pfinal=0.712) and intervertebral height (Ppost=0.363, Pfinal=0.094). The final fusion rates were 96.7% (cage group) and 86.4% (non- cage group) respectively, and there was no statistical difference (P = 0.553). Conclusion Local bone graft has the same advantages as a cage in unilateral PLIF. Comparing with local bone graft using cage, we believe that the local bone graft is a more ideal way in unilateral PLIF, and decrease operation cost.

Objective Fuzi Banxia is one of eighteen antagonisms, previous studies have shown that the incompatibility could play special effects in the specific condition of diseases and appropriate compatible environment. The present study aims to evaluate the toxicity-efficacy of ginseng combined with Fuzi Banxia incompatibility intervening in the heart failure stage of cor pulmonale and to explore its mechanism. Methods Monocrotaline (MCT)-induced cor pulmonale were used in this study. Ultra high-resolution small animal ultrasound real-time imaging system and the right heart catheterization were used to estimate cardiac function. Semi automatic biochemical analyzer was used to test myocardial enzyme LDH, CK, and CK-MB in serum. The heart tissues were stained with HE, and TUNEL assay was used to assess the pathomorphological changes and myocardial apoptosis. The expression of hypertrophy and apoptosis associated genes: ANP, BNP, β-MHC, Bax, and Bcl-2 in the right ventricle were determined by RT-PCR. Results Fuzi Banxia combined with ginseng obviously attenuated mortality, decreased RVHI, and increased cardiac index; RVSP and mPAP were significantly reduced, and EF and FS were raised obviously; Myocardial enzymes LDH, CK, and CK-MB were pronounced attenuated; heart diameter reduced, right ventricular dilatation was significantly decreased, inflammatory cell infiltration notably reduced, and cardiac apoptosis rate was decreased obviously. Meanwhile, the expression of hypertrophy-related ANP, BNP, and β-MHC mRNA were up-regulated, the expression of apoptosis-related Bax mRNA was down-regulated, and the expression of anti-apoptosis-related Bcl-2 mRNA and Bcl-2/Bax ratio were up-regulated. Conclusion Ginseng compatible environment could attenuate cardiac toxicity of Fuzi Banxia incompatibility intervening in the heart failure stage of cor pulmonale, and improve cardiac function, which may be related to the expression of hypertrophy and apoptosis associated genes, and thus delay the occurrence and development of heart failure.

In the study, a software program named “SUPER CE/SE” is developed for the simulation of hypervelocity impact problems with large deformations, high strain rates and spall fractures. In the software program, an Eulerian method consisting of an improved CE/SE (Space-time Conservation Element and Solution Element Method) scheme is used. A void growth model which takes the Bauschinger Effect (BE) into account and a newly proposed front tracking method are adopted in the simulation. The formation and propagation of a crack is described by a newly developed automatic crack growth algorithm. Numerical simulation of spall fracture in a plate when impacted by a spherical projectile at a velocity of 6.0 km/s is carried out. The numerical results are in qualitative agreement with the corresponding experimental data. It turns out that the BE has obvious influence on the length of the crack and better agreement with the experiment is obtained when the BE is considered. It is also validated that the newly proposed front tracking method is feasible and reliable for representing the cracks in the problems with large deformation and high strain rates. According to those research results, it is proved that the software program SUPER CE/SE is robust and effective in the simulation of hypervelocity impact problems.

Crashworthiness requirement of fuel tanks is one of the important requirements in helicopter designs. The relations among the protection frame, textile layer and rubber layer of the fuel tank are introduced. Two appropriate FE models are established, one is for an uncovered helicopter fuel tank without protection frame, and the other is for fuel tank with protection frame. The dynamic responses of the two types of fuel tanks impinging on the ground with velocities of 17.3 m/s are numerically simulated for the purpose of analyzing energy-absorbing capabilities of the textile layer and protection frame. The feasibility of the current crashworthiness design of the fuel tank is examined though comparing the dynamic response behaviors of the two fuel tanks.

The details of the special three-dimensional micro-nano scale ripples with a period of hundreds of microns on the surfaces of a Zr-based and a La-based metallic glass irradiated separately by single laser pulse are investigated. We use the small-amplitude capillary wave theory to unveil the ripple formation mechanism through considering each of the molten metallic glasses as an incompressible viscous fluid. A generalized model is presented to describe the special morphology, which fits the experimental result well. It is also revealed that the viscosity brings about the biggest effect on the monotone decreasing nature of the amplitude and the wavelength of the surface ripples. The greater the viscosity is, the shorter the amplitude and the wavelength are.

The mechanism of the shift of the band-gap in phononic crystal (PC) with different initial confining pressures is studied experimentally and numerically. The experimental results and numerical analysis simultaneously indicate that the confining pressure can efficiently tune the location in and the width of the band-gap. The present work provides a basis for tuning the band-gap of phononic crystal in engineering applications.

Theoretical analysis and numerical calculations of Love wave propagation in layered graded composites with imperfectly bonded interface are described in this paper. On the basis of WKB method, the approximate analytic solutions for Love waves are obtained. By the interface shear spring model, the dispersion relations for Love waves in layered graded composite structures with rigid, slip, and imperfectly bonded interfaces are given, and the effects of the interface conditions on the phase velocities of Love waves in SiC/Al layered graded composites are discussed. Numerical analysis shows that the phase velocity decreases when the defined flexibility parameter is greater. For the general imperfectly bonded interface, the phase velocity changes in the range of the velocities for the rigid and slip interface conditions.