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In this work, we find that Al cladding on Nb microstrip resonators is an efficient way to suppress nonlinear responses induced by local Joule heating, resulting in improved microwave power handling capability. This improvement is likely due to the proximity effect between the Al and the Nb layers. The proximity effect is found to be controllable by tuning the thickness of the Al layer. We show that improving the film quality is also helpful as it enhances the microwave critical current density, but it cannot eliminate the local heating. [ABSTRACT FROM AUTHOR]

This study aims to investigate the fixation strength of unilateral cortical bone trajectory screw fixation (UCBT) and UCBT with contralateral translaminar facet screw fixation (UCBT-TFS) by repeating the verification of three finite element models. Three healthy female models of the lumbosacral spine were constructed. For each of them, four transforaminal lumbar interbody fusion (TLIF) models with the following instruments were created: bilateral traditional trajectory pedicle screw fixation (TT), bilateral cortical bone trajectory screw fixation (CBT), UCBT, and UCBT-TFS. A 150-N compressive load with 10 N/m moments was applied to simulate flexion, extension, lateral bending, and axial rotation. The range of motion (ROM), the stress of the cages, and the stress of the posterior fixations were compared. TT and UCBT-TFS had a similar low ROM compared to the intact models, and CBT showed a higher ROM in lateral bending. UCBT resulted in the highest ROM under all loading conditions, especially in lateral bending (116% and 170% greater than TT in left bending and right bending). UCBT induced a significant increase in the peak stress of cages and instruments, followed by CBT and UCBT-TFS, and the lowest mean values were observed for TT. Among the four different fixation techniques, TT offered the highest fixation strength and lowest implant stress, followed by UCBT-TFS and CBT, while UCBT was the least stable and resulted in increased stress of the screws and cages. UCBT-TFS improved biomechanical stability and appeared to be a less invasive alternative in well-selected patients with single-level TLIF., Competing Interests: None., (AJTR Copyright © 2020.)

Objective: To establish osteoblast-osteoclast cell co-culture system in a Transwell chamber, and detect cell viability of osteoblasts and osteoclasts in system., Methods: Osteoblast MC3T3-E1 and mouse monocytes RAW264.7 were cultivated in vitro. RANKL-induced mouse RAW264.7 monocytes differentiated into mature osteoclasts, osteoblast-osteoclast cell co-culture system was established in Transwell chamber. Cell activity of osteoblasts and osteoclasts were detected by CCK-8 experimenting, Alizarin Red staining, TRAP staining. The expression of OPG, ALP, RANKL, TGF-b1 gene and RANKL protein in osteoblast MC3T3-E1 were detected by PCR, Western-Blot methods. Also, the expression of RANK, NF-κB in gene and protein level in osteoclast were measured through the same method respectively., Results: The co-culture system of Mouse MC3T3-E1 cells and RAW264.7 cell were established in Transwell chamber. Co-culture system affected cell division activities of osteoblasts and osteoclasts. Differentiation of osteoblasts were increased, while differentiation of osteoclast division were slight decreased under microscope observation. OPG (0.65±0.08) and ALP (0.16±0.01) gene expression of co-culture system were less than single culture OPG(1.00±0.08) and ALP (1.01±0.16); TGF-b1(4.42±0.21) and RANKL(4.12±1.04) of osteoblasts in co-culture system were higher than TGF-b1(1.00±0.10) and RANKL(1.00±0.09) under single culture. However, gene expression of RANK(0.63±0.06) and NF-κB(0.64±0.08) in co-culture system were decreased than RANK(1.00±0.08) and NF-κB(1.00±0.09), in single culture, and had significant differences. Similarly, protein expression of OPG(0.43±0.05) and NF-κB(0.59±0.05) of co-culture system were less than OPG(0.84±0.06) and NF-κB(1.13±0.03) of single culture. While RANKL protein expression (0.54±0.03)of co-culture system was more than single culture RANKL(0.31±0.03), and had statistically differences, which was in agreement of the trend of gene expression change., Conclusions: Co-culture system of mouse MC3T3-E1 cells and RAW264.7 cell was viable in Transwell chamber, and the activity of osteoblasts is higher than osteoclasts in co-culture system., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© 2018 by the China Journal of Orthopaedics and Traumatology Press.)

Objective: To investigate the diagnostic value of clinical manifestation, laboratory examination and imaging changes for pyogenic spondylitis and to summarize the clinical characteristics of patients with pyogenic spondylitis., Methods: The clinical data, of 20 patients with pyogenic spondylitis were diagnosed by histopathological examination from March 2012 to March 2015, were retrospectively analyzed. There were 9 males and 11 females, aged from 43 to 72 years old with an average of 58.9 years. Included 3 cases of cervical vertebrae, 7 cases of thoracic vertebrae, 10 cases of lumbar vertebrae. Patients of blood analysis, erythrocyte sedimentation rate(ESR), C reactive protein(CRP), X rays, CT and MRI were performed before treatment. Visual analogue scale (VAS) was used to evaluate the pain of patients suffering from vertebral pain., Results: All the patients had suffered from vertebral pain before treatment. VAS was 9 points in 4 cases, 8 points in 6 cases, 7 points in 1 case, 3 points in 6 cases, and 2 points in 3 cases. Among them, 7 patients complicated with neurological symptoms, 11 with aggravating night pain, 10 with fever. WBC and Neutrophil count (NEU) of 5 cases were increased and other 15 cases were normal;CRP of 19 cases were increased and 1 case was normal;ESR of all 20 cases were increased. X rays showed the intervertebral space narrowing in all 20 cases, 13 cases complicated with destruction of vertebral body; CT showed the lesions of vertebral body in the 20 cases and complicated with destruction, sclerosis of sclerotin; MRI showed that the lesions of the vertebral body in the T1 image had uneven medium low signal, in the T2 image of the 16 cases had uneven high signal and 2 cases had uniform and high signal, 2 cases had main high signal compliated with mixed signal. Thirteen patients underwent surgical treatment and 7 patients received conservative treatment, and the patients left hospital while VAS had significantly improved after treatment., Conclusions: Pyogenic spondylitis is easy to be misdiagnosed or missed in clinic. It can be combined with the clinical manifestations, laboratory examination and imaging characteristics in order to make a definite diagnosis for purulent spondylitis in early., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.