Objective: To investigate the prevalence of myco-plasma infections and the sensitivity to antibiotics among patients with nongonococcal urethritis or cer-vicitis (NGU) in Chongqing. Methods: 387 NGU cases with mycopla...Objective: To investigate the prevalence of myco-plasma infections and the sensitivity to antibiotics among patients with nongonococcal urethritis or cer-vicitis (NGU) in Chongqing. Methods: 387 NGU cases with mycoplasma-positive results upon culture were analysed retrospectively. RESULTS: The majority of patients with mycoplasma infections were in the 20-40 year old age group. No significant difference was found between males and females. Ureaplasma urealyticum is the main pathogen of these NGU cases and no clear relationship between its concentration and pathogenic ability was noted. Drug sensitivity was tested against nine antibiotics; the sensitivity rates to josamycim, minocycline and doxycycline were 94.06%, 88.89% and 86.82% respectively, while the resistance rates to lincomycin, ofloxacin, azithromycin and roxthromycin were 74.94%, 42.12%, 41.60% and 40.31% in turn. Conclusions: Josamycin, minocycline and doxycycline could be used as the first choice to treat NGU with mycoplasma infections in Chongqing. It is important to select antibiotics for NGU treatment with mycoplasma infections based on the results of drug sensitivity tests.展开更多
This paper presents two comparisons or tests for a Lagrangian model of zooplankton dispersion:numerical schemes and time steps.Firstly,we compared three numerical schemes using idealized circulations.Results show that...This paper presents two comparisons or tests for a Lagrangian model of zooplankton dispersion:numerical schemes and time steps.Firstly,we compared three numerical schemes using idealized circulations.Results show that the precisions of the advanced Adams-Bashfold-Moulton(ABM) method and the Runge-Kutta(RK) method were in the same order and both were much higher than that of the Euler method.Furthermore,the advanced ABM method is more efficient than the RK method in computational memory requirements and time consumption.We therefore chose the advanced ABM method as the Lagrangian particle-tracking algorithm.Secondly,we performed a sensitivity test for time steps,using outputs of the hydrodynamic model,Symphonie.Results show that the time step choices depend on the fluid response time that is related to the spatial resolution of velocity fields.The method introduced by Oliveira et al.in 2002 is suitable for choosing time steps of Lagrangian particle-tracking models,at least when only considering advection.展开更多
Fast and accurate identification of unknown pollution sources plays a crucial role in the emergency response and source control of air pollution.In this work,the applicability of a previously proposed two-step inversi...Fast and accurate identification of unknown pollution sources plays a crucial role in the emergency response and source control of air pollution.In this work,the applicability of a previously proposed two-step inversion method is investigated with sensitivity experiments and real data from the first release of the European Tracer Experiment(ETEX-1).The two-step inversion method is based on the principle of least squares and carries out additional model correction through the residual iterative process.To evaluate its performance,its retrieval results are compared with those of two other existing algorithms.It is shown that for those cases with richer measurements,all three methods are less sensitive to errors,while for cases where measurements are sparse,their retrieval accuracy will rapidly decrease as errors increase.From the results of sensitivity experiments,the new method provides higher estimation accuracy and a more stable performance than the other two methods.The new method presents the smallest maximum location error of 18.20 km when the amplitude of the measurement error increases to 100%,and 22.67 km when errors in the wind fields increase to 200%.Moreover,when applied to ETEX-1 data,the new method also exhibits good performance,with a location error of 4.71 km,which is the best estimation with respect to source location.展开更多
文摘Objective: To investigate the prevalence of myco-plasma infections and the sensitivity to antibiotics among patients with nongonococcal urethritis or cer-vicitis (NGU) in Chongqing. Methods: 387 NGU cases with mycoplasma-positive results upon culture were analysed retrospectively. RESULTS: The majority of patients with mycoplasma infections were in the 20-40 year old age group. No significant difference was found between males and females. Ureaplasma urealyticum is the main pathogen of these NGU cases and no clear relationship between its concentration and pathogenic ability was noted. Drug sensitivity was tested against nine antibiotics; the sensitivity rates to josamycim, minocycline and doxycycline were 94.06%, 88.89% and 86.82% respectively, while the resistance rates to lincomycin, ofloxacin, azithromycin and roxthromycin were 74.94%, 42.12%, 41.60% and 40.31% in turn. Conclusions: Josamycin, minocycline and doxycycline could be used as the first choice to treat NGU with mycoplasma infections in Chongqing. It is important to select antibiotics for NGU treatment with mycoplasma infections based on the results of drug sensitivity tests.
基金Supported by the Project Lagrangian Zooplankton Computation and Experiment (CNRS Programme EC2CO)the National Natural Science Fundation of China (Nos. 40821004,40706059)
文摘This paper presents two comparisons or tests for a Lagrangian model of zooplankton dispersion:numerical schemes and time steps.Firstly,we compared three numerical schemes using idealized circulations.Results show that the precisions of the advanced Adams-Bashfold-Moulton(ABM) method and the Runge-Kutta(RK) method were in the same order and both were much higher than that of the Euler method.Furthermore,the advanced ABM method is more efficient than the RK method in computational memory requirements and time consumption.We therefore chose the advanced ABM method as the Lagrangian particle-tracking algorithm.Secondly,we performed a sensitivity test for time steps,using outputs of the hydrodynamic model,Symphonie.Results show that the time step choices depend on the fluid response time that is related to the spatial resolution of velocity fields.The method introduced by Oliveira et al.in 2002 is suitable for choosing time steps of Lagrangian particle-tracking models,at least when only considering advection.
基金supported by the National Key R&D Program of China[grant numbers 2017YFC1501803 and 2017YFC1502102].
文摘Fast and accurate identification of unknown pollution sources plays a crucial role in the emergency response and source control of air pollution.In this work,the applicability of a previously proposed two-step inversion method is investigated with sensitivity experiments and real data from the first release of the European Tracer Experiment(ETEX-1).The two-step inversion method is based on the principle of least squares and carries out additional model correction through the residual iterative process.To evaluate its performance,its retrieval results are compared with those of two other existing algorithms.It is shown that for those cases with richer measurements,all three methods are less sensitive to errors,while for cases where measurements are sparse,their retrieval accuracy will rapidly decrease as errors increase.From the results of sensitivity experiments,the new method provides higher estimation accuracy and a more stable performance than the other two methods.The new method presents the smallest maximum location error of 18.20 km when the amplitude of the measurement error increases to 100%,and 22.67 km when errors in the wind fields increase to 200%.Moreover,when applied to ETEX-1 data,the new method also exhibits good performance,with a location error of 4.71 km,which is the best estimation with respect to source location.