叶端定时是航空发动机叶片叶端振动非接触测量的有效手段,但其采样模式决定了所采信号具有高度欠采样特征,需要进行抗混叠频谱分析从而提取转子叶片固有频率这一关键指标。利用了前向平滑策略的改进多重信号分类法(multiple sIgnal clas...叶端定时是航空发动机叶片叶端振动非接触测量的有效手段,但其采样模式决定了所采信号具有高度欠采样特征,需要进行抗混叠频谱分析从而提取转子叶片固有频率这一关键指标。利用了前向平滑策略的改进多重信号分类法(multiple sIgnal classification,MUSIC)能实现抗混叠但无法充分发挥平滑方法的优势。因此,提出适用于叶端定时信号处理的前后向平滑MUSIC法,通过建立传感器的对称布局条件,利用前后向平滑方法代替前向平滑方法,得到更准确的自相关矩阵估计,进而提高叶片固有频率估计性能,并通过仿真和试验验证了在样本数量、算法参数等相同的情况下,前后向平滑MUSIC法的混叠与噪声抑制能力得到了提升。展开更多
采用简单的一步溶剂热法合成了In_(2)O_(3)立方体,并利用X-射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscopy,SEM)、透射电子显微镜(Transmission electron microscopy,TEM)、X射线光电子能谱(X-ray phot...采用简单的一步溶剂热法合成了In_(2)O_(3)立方体,并利用X-射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscopy,SEM)、透射电子显微镜(Transmission electron microscopy,TEM)、X射线光电子能谱(X-ray photoelectron spectra,XPS)和N2吸附-脱附技术对该In_(2)O_(3)立方体的结构及形貌进行了表征。制备的In_(2)O_(3)立方体尺寸范围在1~5μm。将In_(2)O_(3)立方体制成传感器,测试其对甲苯、丙酮、氯苯、苯、乙醇、二甲苯、甲醇、异丙醇和二氧化氮(NO_(2))气体的气敏性能。结果表明,在最佳工作温度92℃时,In_(2)O_(3)传感器对NO_(2)有良好的气体选择性及灵敏度,对10×10^(-6) NO_(2)气体的响应值为187.7,最低检出限为0.6×10^(-6)。基于In_(2)O_(3)立方体的传感器具有良好的稳定性、重现性和抗湿性,有望实现在实际的复杂环境中对痕量NO_(2)气体的低温检测。展开更多
Introduction: Choriocarcinoma is an aggressive tumor, whose incidence is 0.18 per 100,000 women between the ages of 15 and 49 years [1]. Although its prognosis has improved with the development of chemotherapy regimen...Introduction: Choriocarcinoma is an aggressive tumor, whose incidence is 0.18 per 100,000 women between the ages of 15 and 49 years [1]. Although its prognosis has improved with the development of chemotherapy regimens, the mortality rate of patients with brain metastases is reportedly 29.7% [2]. After chemotherapy, most often, the reappearance of masses in pulmonary is considered to be a sign of relapse. Case presentation: The patient was a 32-year-old Asian Chinese female who delivered a dead male infant at 33 weeks gestation. The placenta appeared to be normal. The major presentation was a haemorrhage of the vagina. The patient received combined treatment with systematic multi-agent chemotherapy and whole-brain radiation therapy at the General Hospital of Hebei Province and achieved complete remission. Two years after remission, a chest CT scan revealed a mass in the right lung that had become larger over 6 months. The patient’s serum β-human chorionic gonadotropin (β-HCG) level was normal, and the tuberculosis infected T lymphocyte spot (T-SPOT.TB) tests were positive. The patient was started on anti-tuberculosis therapy, after which the size of her right lung mass decreased. Conclusion: Lung masses after choriocarcinoma require extensive laboratory and imaging exams to exclude recurrence. This case highlights the importance of differential diagnoses of lung masses in patients with choriocarcinomas. Imaging studies, β-HCG and local lesion resection should be employed to rule out choriocarcinoma recurrence.展开更多
Objective:To investigate the protective effects and mechanisms of action of dexamethasone and Salvia miltiorrhiza on multiple organs in rats with severe acute pancreatitis (SAP). Methods:The rats were divided into sha...Objective:To investigate the protective effects and mechanisms of action of dexamethasone and Salvia miltiorrhiza on multiple organs in rats with severe acute pancreatitis (SAP). Methods:The rats were divided into sham-operated, model control, dexamethasone treated, and Salvia miltiorrhiza treated groups. At 3, 6, and 12 h after operation, the mortality rate of different groups, pathological changes, Bcl-2-associated X protein (Bax) and nuclear factor-κB (NF-κB) protein expression levels in multiple organs (the pancreas, liver, kidneys, and lungs), toll-like receptor 4 (TLR-4) protein levels (only in the liver), intercellular adhesion molecule 1 (ICAM-1) protein levels (only in the lung), and terminal deoxynucleotidy transferase mediated deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) staining expression levels, as well as the serum contents of amylase, glutamate-pyruvate transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), blood urea nitrogen (BUN), and creatinine (CREA) were observed. Results:The mortality rate of the dexamethasone treated group was significantly lower than that of the model control group (P<0.05). The pathological changes in multiple organs in the two treated groups were relieved to different degrees (P<0.05 and P<0.01, respectively), the expression levels of Bax and NF-κB proteins, and apoptotic indexes of multiple organs were reduced (P<0.05 and P<0.01, respectively). The contents of amylase, GPT, GOT, BUN, and CREA in the two treated groups were significantly lower than those in model control groups (P<0.05 and P<0.01, respectively). The expression level of ICAM-1 protein in the lungs (at 3 and 12 h) in the dexamethasone treated group was significantly lower than that in the Salvia miltiorrhiza treated group (P<0.05). The serum contents of CREA (at 12 h) and BUN (at 6 h) of the Salvia miltiorrhiza treated group were significantly lower than those in the dexamethasone treated group (P<0.05). Conclusions:Both dexamethasone and Salvia miltiorrhiza can reduce the inflammatory reaction, regulate apoptosis, and thus protect multiple organs of rats with SAP.展开更多
文摘叶端定时是航空发动机叶片叶端振动非接触测量的有效手段,但其采样模式决定了所采信号具有高度欠采样特征,需要进行抗混叠频谱分析从而提取转子叶片固有频率这一关键指标。利用了前向平滑策略的改进多重信号分类法(multiple sIgnal classification,MUSIC)能实现抗混叠但无法充分发挥平滑方法的优势。因此,提出适用于叶端定时信号处理的前后向平滑MUSIC法,通过建立传感器的对称布局条件,利用前后向平滑方法代替前向平滑方法,得到更准确的自相关矩阵估计,进而提高叶片固有频率估计性能,并通过仿真和试验验证了在样本数量、算法参数等相同的情况下,前后向平滑MUSIC法的混叠与噪声抑制能力得到了提升。
文摘采用简单的一步溶剂热法合成了In_(2)O_(3)立方体,并利用X-射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscopy,SEM)、透射电子显微镜(Transmission electron microscopy,TEM)、X射线光电子能谱(X-ray photoelectron spectra,XPS)和N2吸附-脱附技术对该In_(2)O_(3)立方体的结构及形貌进行了表征。制备的In_(2)O_(3)立方体尺寸范围在1~5μm。将In_(2)O_(3)立方体制成传感器,测试其对甲苯、丙酮、氯苯、苯、乙醇、二甲苯、甲醇、异丙醇和二氧化氮(NO_(2))气体的气敏性能。结果表明,在最佳工作温度92℃时,In_(2)O_(3)传感器对NO_(2)有良好的气体选择性及灵敏度,对10×10^(-6) NO_(2)气体的响应值为187.7,最低检出限为0.6×10^(-6)。基于In_(2)O_(3)立方体的传感器具有良好的稳定性、重现性和抗湿性,有望实现在实际的复杂环境中对痕量NO_(2)气体的低温检测。
文摘Introduction: Choriocarcinoma is an aggressive tumor, whose incidence is 0.18 per 100,000 women between the ages of 15 and 49 years [1]. Although its prognosis has improved with the development of chemotherapy regimens, the mortality rate of patients with brain metastases is reportedly 29.7% [2]. After chemotherapy, most often, the reappearance of masses in pulmonary is considered to be a sign of relapse. Case presentation: The patient was a 32-year-old Asian Chinese female who delivered a dead male infant at 33 weeks gestation. The placenta appeared to be normal. The major presentation was a haemorrhage of the vagina. The patient received combined treatment with systematic multi-agent chemotherapy and whole-brain radiation therapy at the General Hospital of Hebei Province and achieved complete remission. Two years after remission, a chest CT scan revealed a mass in the right lung that had become larger over 6 months. The patient’s serum β-human chorionic gonadotropin (β-HCG) level was normal, and the tuberculosis infected T lymphocyte spot (T-SPOT.TB) tests were positive. The patient was started on anti-tuberculosis therapy, after which the size of her right lung mass decreased. Conclusion: Lung masses after choriocarcinoma require extensive laboratory and imaging exams to exclude recurrence. This case highlights the importance of differential diagnoses of lung masses in patients with choriocarcinomas. Imaging studies, β-HCG and local lesion resection should be employed to rule out choriocarcinoma recurrence.
基金Project (No. 2010382) supported by the Foundation for the Excellent Middle-Aged and Talented Young Persons of Zhejiang Province"151", China
文摘Objective:To investigate the protective effects and mechanisms of action of dexamethasone and Salvia miltiorrhiza on multiple organs in rats with severe acute pancreatitis (SAP). Methods:The rats were divided into sham-operated, model control, dexamethasone treated, and Salvia miltiorrhiza treated groups. At 3, 6, and 12 h after operation, the mortality rate of different groups, pathological changes, Bcl-2-associated X protein (Bax) and nuclear factor-κB (NF-κB) protein expression levels in multiple organs (the pancreas, liver, kidneys, and lungs), toll-like receptor 4 (TLR-4) protein levels (only in the liver), intercellular adhesion molecule 1 (ICAM-1) protein levels (only in the lung), and terminal deoxynucleotidy transferase mediated deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) staining expression levels, as well as the serum contents of amylase, glutamate-pyruvate transaminase (GPT), glutamic-oxaloacetic transaminase (GOT), blood urea nitrogen (BUN), and creatinine (CREA) were observed. Results:The mortality rate of the dexamethasone treated group was significantly lower than that of the model control group (P<0.05). The pathological changes in multiple organs in the two treated groups were relieved to different degrees (P<0.05 and P<0.01, respectively), the expression levels of Bax and NF-κB proteins, and apoptotic indexes of multiple organs were reduced (P<0.05 and P<0.01, respectively). The contents of amylase, GPT, GOT, BUN, and CREA in the two treated groups were significantly lower than those in model control groups (P<0.05 and P<0.01, respectively). The expression level of ICAM-1 protein in the lungs (at 3 and 12 h) in the dexamethasone treated group was significantly lower than that in the Salvia miltiorrhiza treated group (P<0.05). The serum contents of CREA (at 12 h) and BUN (at 6 h) of the Salvia miltiorrhiza treated group were significantly lower than those in the dexamethasone treated group (P<0.05). Conclusions:Both dexamethasone and Salvia miltiorrhiza can reduce the inflammatory reaction, regulate apoptosis, and thus protect multiple organs of rats with SAP.
