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Background Degeneration of sacroiliac joints (SIJ) is common in the general population, which associates with age, gender and body mass index (BMI). This degenerative disease relates to various lumbar disorders. Lumbar facet joint osteoarthritis (LFJOA) is highly prevalent, but relationship between this disease and SIJ degeneration remains poorly evaluated. Objectives This study aimed to investigate the relation between LFJOA and SIJ degeneration. We hypothesized that LFJOA patients might suffer more serious SIJ degeneration, thus multiple linear regression was employed to compare the effect of LFJOA and demographic characteristics on degeneration of SIJ. Methods We reviewed pelvic and lumbar computed tomography (CT) examinations of LFJOA patient with low back pain (LBP) through a picture archiving and communication system. The controls were age, gender and BMI-matched individuals who were free of LFJOA and LBP, and underwent pelvic and whole abdomen CT scans due to the non-musculoskeletal symptoms. Severity of SIJ degeneration was scored using a quantitative method which has been descripted by Backlund et al [1]. LFJOA was graded using a method which has been mentioned by Weishaupt et al [2]. Briefly, this method concerns facet joint space, osteophytes, hypertrophy of the articular processes, and subarticular bone erosions, which ranges from 0 to 3 for a joint. If there is a discrepancy between 2 joints in the same level, the greater one was used. LFJOA was defined at least one level ≥2 from L1-2 to L5-S1. Scores of SIJ degeneration were compared between LFJOA patients and the controls. Correlation analysis between SIJ degeneration score and number of LFJOA levels, number of LFJOA joints, sum of LFJOA grades were performed. Stepwise multiple linear regression model was used to find the most important contributor of SIJ degeneration among LFJOA, gender, age and BMI. Results (1) CT examinations of 992 LFJOA patients and 399 controls were reviewed. (2) Score of SIJ degeneration in LFJOA patients were higher than that of the controls (8.85±2.94 vs. 4.31±2.52, P Conclusion LFJOA patients suffers more significant SIJ degeneration, and more severe LFJOA leads to more serious SIJ degeneration. Influence of LFJOA on SIJ degeneration is stronger than demographic characteristics. References [1] Backlund J, Clewett Dahl E, Skorpil M. Is CT indicated in diagnosing sacroiliac joint degeneration? Clin Radiol 2017;72(8):693.e9-693.e13. [2] Weishaupt D, Zanetti M, Boos N, et al. MR imaging and CT in osteoarthritis of the lumbar facet joints. Skeletal Radiol 1999; 28: 215-219. Acknowledgement None. Disclosure of Interests None declared

Lower hybrid (LH) wave current drive efficiency on our HT-7 tokamak has been investigated based on the hot electrical conductivity theory. The interaction of the residual toroidal electric field with fast electrons has been included in the determination of current drive efficiency. The LH wave power scan was performed in the plasma parameter ranges of Ip = 50–156 kA, e = 0.5×1019–1.6×1019 m−3, PLH = 50–350 kW. The current drive efficiency is derived to be about 0.1×1019–0.4×1019 Am−2W−1 on the HT-7 tokamak, which depends on the electron density and the LH wave phase velocity. At the electron density of about 1.5×1019 m−3, with the LH wave parallel refraction index peaked at 1.8, the highest current drive efficiency was obtained. A more generally normalized method is introduced to analyse the experimental data, which combines all the data in one curve. The normalized parameters are independent of the plasma parameters.

BACKGROUND: Direct application of insect cadavers infected with entomopathogenic nematodes (EPN) can successfully control target pest insects. Little is known about the effects of environmental factors (desiccation and temperature) on the production process for infective juveniles (IJ) in insects. RESULTS: We examined the effects of desiccation time and cold storage (6.7°C) on IJ production of the nematode Steinernemacarpocapsae in Galleriamellonella cadavers at 30.8 and 57% humidity. Under desiccation, the IJ yield in cadavers increased gradually and reached a maximum on day5. IJ yield gradually declined from day6 onwards and was almost zero by day15. In general, cold storage at 6.7°C caused negative effects on IJ production in desiccated cadavers. Approximately 56h post infection was the time at which nematodes were most sensitive to low temperatures during development in cadavers. Five-day desiccated cadavers generated higher mortality and more rapid death of Galleriamellonella larvae than using newly (day0) desiccated cadavers. CONCLUSION: This study describe methods of optimizing rearing techniques such as desiccation and cold storage to promote the mass production and application of EPN- infected host cadavers for the field control of insect pests. © 2013 Society of Chemical Industry.

Considering the attenuation, severing, taper and magnetic admittance, the self-consistent working equations are presented, which describe the operation of 3D nonlinear beam-wave interaction for helix traveling wave tube based on periodic structure characteristic and Poynting's theorem. Using Fourier transform from time-dependent current to ac current consisting of a series of wave frequencies, the space fields are obtained through weighing charge particles to fixed meshes with the help of particle_in_cell technique. The model also computes 3D electronic tracks and helix interception current, the electronic energy spectrum of spent beam are represented, which is helpful for designing multistage depressed collector （MDC）. Calculation of Ku-band TWT in IECAS was shown to be in better agreement with experiment, including output power and analysis of MDC.