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For the case that two pursuers intercept an evasive target, the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target, which performs a bang For the case that two pursuers intercept an evasive target, the cooperative strategies and state estimation methods taken by pursuers can seriously affect the guidance accuracy for the target, which performs a bang-bang evasive maneuver with a random switching time. Combined Fast multiple model adaptive estimation (Fast MMAE) algorithm, the cooperative guidance law takes detection configuration affecting the accuracy of interception into consideration. Introduced the detection error model related to the line-of-sight (LOS) separation angle of two interceptors, an optimal cooperative guidance law solving the optimization problem is designed to modulate the LOS separation angle to reduce the estimation error and improve the interception performance. Due to the uncertainty of the target bang-bang maneuver switching time and the effective fitting of its multi-modal motion, Fast MMAE is introduced to identify its maneuver switching time and estimate the acceleration of the target to track and intercept the target accurately. The designed cooperative optimal guidance law with Fast MMAE has better estimation ability and interception performance than the traditional guidance law and estimation method via Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to differentiate tuberculous peritonitis (TBP) from peritoneal carcinomatosis (PC) using a visual positron-emission tomography/computed tomography (PET/CT) scoring system based on mesenteric fluorodeoxyglucose (FDG) uptake.Methods: PET/CT scans from 31 patients with TBP and 92 patients with PC were retrospectively reviewed. A visual PET/CT scoring system for mesenteric FDG uptake was used according to the following characteristics: FDG uptake intensity (low = 0, moderate = 1, high = 2), FDG uptake deposits (uniform = 0, irregular = 1, ascitic = 2), FDG uptake focality (diffuse = 0, segmental = 1, focal = 2), nodularity on the corresponding CT (nonnodular = 0, micronodular = 1, macronodular = 2) and mesenteric lymphadenopathy (absent = 0, lymphadenopathy without FDG uptake = 1, lymphadenopathy with FDG uptake = 2). The FDG uptake intensity, deposits, focality, nodularity and mesenteric lymphadenopathy scores between TBP and PC were compared using chi-square tests. The diagnostic performance of this scoring system for differentiating TBP from PC was analyzed using a receiver operating characteristic (ROC) curve. P < 0.05 was considered statistically significant.Results: Twenty-four patients with TBP (77.4%) and 56 patients with PC (60.9%) had mesenteric FDG uptake (P = 0.095) and were included for evaluation with the visual PET/CT scoring system. PC lesions scored higher than TBP lesions in FDG uptake deposits (P < 0.001), focality (P < 0.001) and nodularity (P < 0.001). No significant differences were observed between PC and TBP lesions in FDG uptake intensity (P = 0.396) and lymphadenopathy (P = 0.074). The total score that combined deposits, focality and nodularity had significant value for differentiating TBP from PC (area under the curve (AUC) = 0.869, P < 0.001), and a cutoff > 1 had a sensitivity (the accuracy for diagnosis of PC) of 80.4% and a specificity (the accuracy for diagnosis of TBP) of 75.0%.Conclusion: A visual PET/CT scoring system based on mesenteric FDG uptake performed well in differentiating between TBP and PC. [ABSTRACT FROM AUTHOR]

Main objective is to explore the characteristics, drug resistance, and risk factors of pathogens in urinary tract infection patients complicated with urinary calculi. A total of 417 patients with urinary calculi who were treated in our hospital from January 2017 to December 2019 were enrolled in this study, including 234 patients with urinary tract infection and 183 patients without urinary tract infection. The midstream urine of 234 patients with urinary tract infection were cultured and used in the drug sensitivity test. Univariate and multivariate logistic regression analysis was used to analyze the risk factors of postoperative urinary tract infection in patients with urinary calculi. A total of 624 strains of pathogens were isolated from the urine samples of 234 patients with postoperative urinary tract infection, of which 386 strains were gram-negative bacteria (61.86 %), 169 strains were gram-positive bacteria (27.08 %), and 69 strains were fungus (11.06 %). In the drug resistance test, the resistance rates of Staphylococcus aureus to tetracycline, rifampicin, and levofloxacin, and the resistance rate of Enterococcus faecium to levofloxacin was low. Enterococcus faecalis had the lowest resistance rate to levofloxacin, followed by azithromycin and gentamicin. The resistance rates of Staphylococcus epidermidis to levofloxacin and vancomycin were low and the resistance rate to erythromycin was 100.00 %. The resistance rate of Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis to meropenem and amikacin, and the resistance rate of Klebsiella pneumoniae and Proteus mirabilis to etilmicin and ceftriaxone were low. Univariate analysis showed that the postoperative urinary tract infection in patients with urinary calculi was related to the age, operation time, postoperative indwelling catheter time, stone size, and preoperative prophylactic use of antibiotics. Multivariate logistic regression analysis showed that the age (=65 y old), operation time (=60 min), postoperative indwelling catheter time (=7 d), and no preoperative prophylactic use of antibiotics were the risk factors of postoperative urinary tract infection in patients with urinary calculi. Patients with urinary calculi were prone to urinary tract infection after the operation. The main pathogens of infection were gram-negative bacteria and gram-positive bacteria, and they were resistant to some antibiotics. Antibiotics should be treated reasonably according to the risk factors of urinary tract infection and the results of the drug sensitivity tests to avoid further aggravation of bacterial drug resistances. [ABSTRACT FROM AUTHOR]

Background: Anterior cervical discectomy and fusion (ACDF) is widely used in the treatment of cervical degenerative disease; however, the variation of cervical sagittal alignment changes after ACDF has been rarely explored. The purpose of this study is to determine the relationship between changes of cervical sagittal alignment after ACDF and spino-pelvic sagittal alignment under Roussouly classification.Methods: A cohort of 133 Chinese cervical spondylotic patients who received ACDF from 2011 to 2012 was recruited. All patients were categorized with Roussouly Classification. Lateral X-ray images of global spine were obtained, and preoperative and postoperative parameters were measured and analyzed, including C2-C7 angles (C2-C7), C0-C7 angles (C0-C7), external auditory meatus (EAM) tilt, sacral slope (SS), thoracic kyphosis (TK), lumbar lordosis (LL), spinal sacral angles (SSA), Superior adjacent inter-vertebral angle (SAIV), inferior adjacent inter-vertebral angle (IAIV) and et al. The Wilcoxon signed-rank test was used for intragroup comparisons preoperatively and at postoperative 48 months.Results: Among the parameters, C2-C7 and C0-C7 showed significant increase, while EAM TK, and IAIV decreased significantly. In type I, EAM and TK decreased significantly, however SS showed a significant increase; in type II, TK showed a significant decrease, but SSA showed a significant increase; in type III, a significant increase of C0-C7 was observed with a significant decrease in EAM, nevertheless, LL, SS and SSA showed significant decreases; and in type IV, C2-C7 showed a significant increase and EAM decreased significantly. The percentage of lordotic alignment in cervical spine increased, which was presenting in type I, III and IV. Nevertheless, the amount of patients with straight cervical alignment increased in type II.Conclusion: The backward movement of head occurs is the compensatory mechanism in cervical sagittal alignment modifications after ACDF. The compensatory alteration of spino-pelvic sagittal alignment varied in different Roussouly type. [ABSTRACT FROM AUTHOR]

A new terahertz (THz) filtering antenna realised by 3D substrate integrated circular waveguide (3D-SICW) is presented. The filtering antenna is designed on a low-temperature co-fired ceramic substrate. Different from traditional planar structure, the direction of power in 3D-SICW is along Z-axis and this will significantly enhance the performance of the devices at THz frequency. The filtering antenna is constructed by two 3D-SICW cavities and a standard substrate integrated waveguide (SIW) cavity, where one SICW cavity and the standard SIW cavity form the bandpass filter by using electric coupling and the other SICW cavity is used as antenna. The results indicate that the passband of filtering antenna range from 170.4 to 177.8 GHz and the gain of antenna is about 5.7 dB. Finally, the filtering antenna is fabricated and measured to verify the simulation prediction. The measured and simulated results are in good agreement at such high frequency. [ABSTRACT FROM AUTHOR]