传统评价方法无法全面地辨识涉及多个交互部件和复杂控制策略的压缩空气储能(Compressed Air Energy Storage,CAES)系统的潜在风险。为了更加全面地辨识CAES系统的潜在风险,研究将系统论过程分析(System-Theoretic Process Analysis,ST...传统评价方法无法全面地辨识涉及多个交互部件和复杂控制策略的压缩空气储能(Compressed Air Energy Storage,CAES)系统的潜在风险。为了更加全面地辨识CAES系统的潜在风险,研究将系统论过程分析(System-Theoretic Process Analysis,STPA)方法引入至先进绝热压缩空气储能系统中并进行风险分析。首先,通过对多种构型的压缩空气储能系统进行效率分析并确定研究对象;其次,定义系统储热过程中系统级事故和危害,构建控制结构模型,并识别可能导致事故的控制动作;最后,从系统控制、组件失效、系统协调不足、人为操作失误等多个维度,分析32个潜在的系统级危险场景,并提出109项针对性的控制措施。此外,选取危害与可操作性研究(Hazard and Operability Study,HAZOP)方法对STPA分析结果进行对比分析与可靠性验证,相比于HAZOP方法28.6%的识别率,STPA方法可有效识别61.5%的系统交互故障,在揭示储能系统复杂交互故障方面展现出了优越性。基于STPA的风险分析对于优化系统设计和提升系统稳定性与可靠性具有重要指导意义,研究为类似新兴能源系统的风险识别提供了参考和借鉴。展开更多
Objective: To analyze the clinical and pathologic features and the treatmentoutcomes of primary lymphoma of respiratory system (PLRS). Methods: The clinical manifestation,imaging changes, pathologic subtypes, treatmen...Objective: To analyze the clinical and pathologic features and the treatmentoutcomes of primary lymphoma of respiratory system (PLRS). Methods: The clinical manifestation,imaging changes, pathologic subtypes, treatment and overall survival of 11 patients with PLRS wereanalyzed retrospectively. Results: Of the 11 patients diagnosed with PLRS by histopathology, thetumor of 2 patients occurred in trachea and the other 9 in lung. Cough, dyspnea and fever were themost frequent symptoms. Mass or infiltrative changes could be found on the chest X-ray and/or CTscan. Two patients were diagnosed as having Hodgkin's Lymphoma (HL) and 9 having non-Hodgkin'sLymphoma (NHL), including 7 patients with low degree NHL [5 of them (55.6%) were mucosa-associatedlymphoid tissue (MALT) lymphoma] and 2 with intermediate degree NHL. Of 10 patients undergoingexploratory thoracotomy and surgical treatment, 8 received adjuvant chemotherapy and 2 adjuvant ofradiotherapy. The remaining patient was subjected to combined chemotherapy. Both of HL patientssurvived more than 5 years without clinical disease. The median survival of MALT lymphoma and othertype of NHL was 39 months and 34 months respectively. Conclusion: Both the clinical manifestationand imaging changes are non-specific. The diagnosis was made through exploratory thoracotomy (10cases) and fiber-optical bronchoscopy (1 case). MALT lymphoma is the most frequent pathologicsubtype. Majority of patients are diagnosed and treated by surgical resection. The prognosis isacceptable.展开更多
AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane...AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane Library,and undertook a meta-analysis to compare the efficacy and safety of laparoscopic hepatectomy V S conventional open liver resection for local hepatolithiasis in the left or right lobe. Intraoperative and postoperative outcomes(time,estimated blood loss,blood transfusion rate,postoperative intestinal function recovery time,length of hospital stay,postoperative complication rate,initial residual stone,final residual stone and stone recurrence) were analyzed systematically.RESULTS A comprehensive literature search retrieved 16 publications with a total of 1329 cases. Meta-analysis of these studies showed that the laparoscopic approach for hepatolithiasis was associated with significantly less intraoperative estimated blood loss [weighted mean difference(WMD): 61.56,95% confidence interval(CI): 14.91-108.20,P = 0.01],lower blood transfusion rate [odds ratio(OR): 0.41,95%CI: 0.22-0.79,P = 0.008],shorter intestinal function recovery time(WMD: 0.98,95%CI: 0.47-1.48,P = 0.01),lower total postoperative complication rate(OR: 0.52,95%CI: 0.39-0.70,P < 0.0001) and shorter stay in hospital(WMD: 3.32,95%CI: 2.32-4.32,P < 0.00001). In addition,our results showed no significant differences between the two groups in operative time(WMD: 21.49,95%CI: 0.27-43.24,P = 0.05),residual stones(OR: 0.79,95%CI: 0.50-1.25,P = 0.31) and stone recurrence(OR: 0.34,95%CI: 0.11-1.08,P = 0.07). Furthermore,with subgroups analysis,our results proved that the laparoscopic approach for hepatolithiasis in the left lateral lobe and left side could achieve satisfactory therapeutic effects. CONCLUSION The laparoscopic approach is safe and effective,with less intraoperative estimated blood loss,fewer postoperative complications,reduced length of hospital stay and shorter intestinal function recovery time than with conventional approaches.展开更多
To perform a systematic review and meta-analysis on clinical outcomes of photodynamic therapy (PDT) in non-resectable cholangiocarcinoma.METHODSIncluded studies compared outcomes with photodynamic therapy and biliary ...To perform a systematic review and meta-analysis on clinical outcomes of photodynamic therapy (PDT) in non-resectable cholangiocarcinoma.METHODSIncluded studies compared outcomes with photodynamic therapy and biliary stenting (PDT group) vs biliary stenting only (BS group) in palliation of non-resectable cholangiocarcinoma. Articles were searched in MEDLINE, PubMed, and EMBASE. Pooled proportions were calculated using fixed and random effects model. Heterogeneity among studies was assessed using the I<sup>2</sup> statistic.RESULTSTen studies (n = 402) that met inclusion criteria were included in this analysis. The P for χ<sup>2</sup> heterogeneity for all the pooled accuracy estimates was > 0.10. Pooled odds ratio for successful biliary drainage (decrease in bilirubin level > 50% within 7days after stenting) in PDT vs BS group was 4.39 (95%CI: 2.35-8.19). Survival period in PDT and BS groups were 413.04 d (95%CI: 349.54-476.54) and 183.41 (95%CI: 136.81-230.02) respectively. The change in Karnofsky performance scores after intervention in PDT and BS groups were +6.99 (95%CI: 4.15-9.82) and -3.93 (95%CI: -8.63-0.77) respectively. Odds ratio for post-intervention cholangitis in PDT vs BS group was 0.57 (95%CI: 0.35-0.94). In PDT group, 10.51% (95%CI: 6.94-14.72) had photosensitivity reactions that were self-limiting. Subgroup analysis of prospective studies showed similar results, except the incidence of cholangitis was comparable in both groups.CONCLUSIONIn palliation of unresectable cholangiocarcinoma, PDT seems to be significantly superior to BS alone. PDT should be used as an adjunct to biliary stenting in these patients.展开更多
We modified the sediment incipient motion in a numerical model and evaluated the impact of this modification using a study case of the coastal area around Weihai, China. The modified and unmodified versions of the mod...We modified the sediment incipient motion in a numerical model and evaluated the impact of this modification using a study case of the coastal area around Weihai, China. The modified and unmodified versions of the model were validated by comparing simulated and observed data of currents, waves, and suspended sediment concentrations(SSC) measured from July 25^(th) to July 26^(th), 2006. A fitted Shields diagram was introduced into the sediment model so that the critical erosional shear stress could vary with time. Thus, the simulated SSC patterns were improved to more closely reflect the observed values, so that the relative error of the variation range decreased by up to 34.5% and the relative error of simulated temporally averaged SSC decreased by up to 36%. In the modified model, the critical shear stress values of the simulated silt with a diameter of 0.035 mm and mud with a diameter of 0.004 mm varied from 0.05 to 0.13 N/m^2, and from 0.05 to 0.14 N/m^2, respectively, instead of remaining constant in the unmodified model. Besides, a method of applying spatially varying fractions of the mixed grain size sediment improved the simulated SSC distribution to fit better to the remote sensing map and reproduced the zonal area with high SSC between Heini Bay and the erosion groove in the modified model. The Relative Mean Absolute Error was reduced by between 6% and 79%, depending on the regional attributes when we used the modified method to simulate incipient sediment motion. But the modification achieved the higher accuracy in this study at a cost of computation speed decreasing by 1.52%.展开更多
文摘传统评价方法无法全面地辨识涉及多个交互部件和复杂控制策略的压缩空气储能(Compressed Air Energy Storage,CAES)系统的潜在风险。为了更加全面地辨识CAES系统的潜在风险,研究将系统论过程分析(System-Theoretic Process Analysis,STPA)方法引入至先进绝热压缩空气储能系统中并进行风险分析。首先,通过对多种构型的压缩空气储能系统进行效率分析并确定研究对象;其次,定义系统储热过程中系统级事故和危害,构建控制结构模型,并识别可能导致事故的控制动作;最后,从系统控制、组件失效、系统协调不足、人为操作失误等多个维度,分析32个潜在的系统级危险场景,并提出109项针对性的控制措施。此外,选取危害与可操作性研究(Hazard and Operability Study,HAZOP)方法对STPA分析结果进行对比分析与可靠性验证,相比于HAZOP方法28.6%的识别率,STPA方法可有效识别61.5%的系统交互故障,在揭示储能系统复杂交互故障方面展现出了优越性。基于STPA的风险分析对于优化系统设计和提升系统稳定性与可靠性具有重要指导意义,研究为类似新兴能源系统的风险识别提供了参考和借鉴。
文摘Objective: To analyze the clinical and pathologic features and the treatmentoutcomes of primary lymphoma of respiratory system (PLRS). Methods: The clinical manifestation,imaging changes, pathologic subtypes, treatment and overall survival of 11 patients with PLRS wereanalyzed retrospectively. Results: Of the 11 patients diagnosed with PLRS by histopathology, thetumor of 2 patients occurred in trachea and the other 9 in lung. Cough, dyspnea and fever were themost frequent symptoms. Mass or infiltrative changes could be found on the chest X-ray and/or CTscan. Two patients were diagnosed as having Hodgkin's Lymphoma (HL) and 9 having non-Hodgkin'sLymphoma (NHL), including 7 patients with low degree NHL [5 of them (55.6%) were mucosa-associatedlymphoid tissue (MALT) lymphoma] and 2 with intermediate degree NHL. Of 10 patients undergoingexploratory thoracotomy and surgical treatment, 8 received adjuvant chemotherapy and 2 adjuvant ofradiotherapy. The remaining patient was subjected to combined chemotherapy. Both of HL patientssurvived more than 5 years without clinical disease. The median survival of MALT lymphoma and othertype of NHL was 39 months and 34 months respectively. Conclusion: Both the clinical manifestationand imaging changes are non-specific. The diagnosis was made through exploratory thoracotomy (10cases) and fiber-optical bronchoscopy (1 case). MALT lymphoma is the most frequent pathologicsubtype. Majority of patients are diagnosed and treated by surgical resection. The prognosis isacceptable.
基金Supported by National Natural Science Foundation of China,No.81372243,No.81570593 and No.81370575Key Scientific and Technological Projects of Guangdong Province,No.2014B020228003 and No.2014B030301041+2 种基金Natural Science Foundation of Guangdong Province,No.2015A030312013Science and Technology Planning Project of Guangzhou,No.201400000001-3,No.201508020262 and No.2014J4100128Science and Technology Planning Project of Guangdong Province,No.2017A020215178
文摘AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane Library,and undertook a meta-analysis to compare the efficacy and safety of laparoscopic hepatectomy V S conventional open liver resection for local hepatolithiasis in the left or right lobe. Intraoperative and postoperative outcomes(time,estimated blood loss,blood transfusion rate,postoperative intestinal function recovery time,length of hospital stay,postoperative complication rate,initial residual stone,final residual stone and stone recurrence) were analyzed systematically.RESULTS A comprehensive literature search retrieved 16 publications with a total of 1329 cases. Meta-analysis of these studies showed that the laparoscopic approach for hepatolithiasis was associated with significantly less intraoperative estimated blood loss [weighted mean difference(WMD): 61.56,95% confidence interval(CI): 14.91-108.20,P = 0.01],lower blood transfusion rate [odds ratio(OR): 0.41,95%CI: 0.22-0.79,P = 0.008],shorter intestinal function recovery time(WMD: 0.98,95%CI: 0.47-1.48,P = 0.01),lower total postoperative complication rate(OR: 0.52,95%CI: 0.39-0.70,P < 0.0001) and shorter stay in hospital(WMD: 3.32,95%CI: 2.32-4.32,P < 0.00001). In addition,our results showed no significant differences between the two groups in operative time(WMD: 21.49,95%CI: 0.27-43.24,P = 0.05),residual stones(OR: 0.79,95%CI: 0.50-1.25,P = 0.31) and stone recurrence(OR: 0.34,95%CI: 0.11-1.08,P = 0.07). Furthermore,with subgroups analysis,our results proved that the laparoscopic approach for hepatolithiasis in the left lateral lobe and left side could achieve satisfactory therapeutic effects. CONCLUSION The laparoscopic approach is safe and effective,with less intraoperative estimated blood loss,fewer postoperative complications,reduced length of hospital stay and shorter intestinal function recovery time than with conventional approaches.
文摘To perform a systematic review and meta-analysis on clinical outcomes of photodynamic therapy (PDT) in non-resectable cholangiocarcinoma.METHODSIncluded studies compared outcomes with photodynamic therapy and biliary stenting (PDT group) vs biliary stenting only (BS group) in palliation of non-resectable cholangiocarcinoma. Articles were searched in MEDLINE, PubMed, and EMBASE. Pooled proportions were calculated using fixed and random effects model. Heterogeneity among studies was assessed using the I<sup>2</sup> statistic.RESULTSTen studies (n = 402) that met inclusion criteria were included in this analysis. The P for χ<sup>2</sup> heterogeneity for all the pooled accuracy estimates was > 0.10. Pooled odds ratio for successful biliary drainage (decrease in bilirubin level > 50% within 7days after stenting) in PDT vs BS group was 4.39 (95%CI: 2.35-8.19). Survival period in PDT and BS groups were 413.04 d (95%CI: 349.54-476.54) and 183.41 (95%CI: 136.81-230.02) respectively. The change in Karnofsky performance scores after intervention in PDT and BS groups were +6.99 (95%CI: 4.15-9.82) and -3.93 (95%CI: -8.63-0.77) respectively. Odds ratio for post-intervention cholangitis in PDT vs BS group was 0.57 (95%CI: 0.35-0.94). In PDT group, 10.51% (95%CI: 6.94-14.72) had photosensitivity reactions that were self-limiting. Subgroup analysis of prospective studies showed similar results, except the incidence of cholangitis was comparable in both groups.CONCLUSIONIn palliation of unresectable cholangiocarcinoma, PDT seems to be significantly superior to BS alone. PDT should be used as an adjunct to biliary stenting in these patients.
基金Supported by the National Natural Science Foundation of China(Nos.41276084,41406100)
文摘We modified the sediment incipient motion in a numerical model and evaluated the impact of this modification using a study case of the coastal area around Weihai, China. The modified and unmodified versions of the model were validated by comparing simulated and observed data of currents, waves, and suspended sediment concentrations(SSC) measured from July 25^(th) to July 26^(th), 2006. A fitted Shields diagram was introduced into the sediment model so that the critical erosional shear stress could vary with time. Thus, the simulated SSC patterns were improved to more closely reflect the observed values, so that the relative error of the variation range decreased by up to 34.5% and the relative error of simulated temporally averaged SSC decreased by up to 36%. In the modified model, the critical shear stress values of the simulated silt with a diameter of 0.035 mm and mud with a diameter of 0.004 mm varied from 0.05 to 0.13 N/m^2, and from 0.05 to 0.14 N/m^2, respectively, instead of remaining constant in the unmodified model. Besides, a method of applying spatially varying fractions of the mixed grain size sediment improved the simulated SSC distribution to fit better to the remote sensing map and reproduced the zonal area with high SSC between Heini Bay and the erosion groove in the modified model. The Relative Mean Absolute Error was reduced by between 6% and 79%, depending on the regional attributes when we used the modified method to simulate incipient sediment motion. But the modification achieved the higher accuracy in this study at a cost of computation speed decreasing by 1.52%.
