The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei （AGN）. We explore the relation between the Doppler factors d of the jet of blazars and their broad line region lumin...The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei （AGN）. We explore the relation between the Doppler factors d of the jet of blazars and their broad line region luminosity LBLR. Since different methods measuring δ might differ substantially, we use data obtained from 3 independent methods and compile 3 samples of sources for each of them, respectively. Two samples consist of blazars, that is, Flat Spectrum Radio Quasars （FSRQs） and BL Lacertae objects （BL Lacs）, and the other consists of BL Lacs. dis one of the most important jet properties and LBLR is thought to be the proxy of the accretion power. Correlation analysis to these samples shows that there exists a significant correlation between δ and LBLR, which supports the idea that the jet powering process is closely linked with the accretion process and provides new evidence for disk-jet connection. Furthermore, the results are consistent with the idea that the Blandford-Znajek mechanism is sufficient for BL Lacs and a hybrid model is needed for FSRQs.展开更多
[Objective] The aim was to summarize the characteristics of refelectivity factors of Doppler radar of the cold front cloud system. [Method] Judging from the characteristics of reflectivity factors, by dint of the new ...[Objective] The aim was to summarize the characteristics of refelectivity factors of Doppler radar of the cold front cloud system. [Method] Judging from the characteristics of reflectivity factors, by dint of the new generation weather radar in Harbin from 2002 to 2007, the features of the reflectivity factors of the cold front cloud system were summarized. [Result] The cloud formed by the cold front was in banded form in general. However, there was void in the cloud and its intensity was uneven. Most fast moving cold front was long and narrow banded echo and basically the radial velocity turned from northwest wind to southwest. With the changes of month, the feature of the reflective rate also changed. In winter, the cold front cloud was in layer form. The feature of the reflectivity factors was weak and in large area. However, the structure was loose and there was space in the echo. Among them, there were several strong echoes. Strong convection cell echo formed in the two sides of the cold front, and it moved with the entire cloud belt. When the dry cold front moved, regional strong convective current formed, mainly by convective cloud and small echo area. Generally, the changes of the wind direction can not be expounded from the radial velocity. However, the intensity of the convection cell was distinct, 'three-body scattering', 'side lobe echo', and 'weak echo', as well as features of super convection cell. [Conclusion] The study provided positive role for the application of Doppler radar in the surveillance of weather in Heilongjiang Province.展开更多
目的:本研究旨在探讨基于经颅多普勒超声(Transcranial doppler,TCD)与颈动脉超声评估急性缺血性卒中患者的预后影响因素。方法:选取2022年1月至2024年1月期间在本院诊断为急性缺血性卒中的患者120例作为研究对象。患者治疗后均随访6个...目的:本研究旨在探讨基于经颅多普勒超声(Transcranial doppler,TCD)与颈动脉超声评估急性缺血性卒中患者的预后影响因素。方法:选取2022年1月至2024年1月期间在本院诊断为急性缺血性卒中的患者120例作为研究对象。患者治疗后均随访6个月,并根据患者预后情况不同,将患者分为预后良好组和预后不良组。采用TCD和颈动脉超声收集患者的血流动力学指标及颈动脉病变参数。收集并对比患者的基线资料。通过Logistic回归分析评估急性缺血性卒中不良预后的影因素。结果:120例患者中,72例(60%)患者预后良好,48例(40%)患者预后不良。预后不良组的年龄明显大于预后良好组(P<0.05),但两组的性别、卒中病因及既往病史均无显著差异。预后良好组的中动脉峰值流速、中动脉平均流速均明显高于预后不良组,而颈动脉内膜-中层厚度、颈动脉狭窄率、不稳定斑块率、美国国立卫生研究院卒中量表(National Institutes of Health Stroke Scale,NIHSS)评分、血糖、总胆固醇(Total cholesterol,TC)、甘油三酯(Triglyceride,TG)、低密度脂蛋白胆固醇(Low density lipoprotein cholesterol,LDL-C)、C反应蛋白(C-reactive protein,CRP)水平均明显低于预后不良组(P<0.05)。Logistic回归分析显示,年龄、NIHSS评分、颈动脉狭窄率、中动脉峰值流速、不稳定斑块、血糖、TC、TG及CRP均是脑卒中不良预后的独立危险因素(P<0.05),中动脉平均流速及颈动脉内膜-中层厚度与不良预后无显著相关性。结论:TCD与颈动脉超声参数与急性缺血性卒中患者的预后相关,颈动脉狭窄率、中动脉峰值流速、不稳定斑块均是脑卒中不良预后的危险因素。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.10973034,10978019,11043002)the State Key Development Program for Basic Research of China(Grant No. 2009CB824800)the Provincial Natural Science Foundation of Yunnan (Grant No.09401145,1012456)
文摘The disk-jet symbiosis is a fundamental problem in our understanding of the Active Galactic Nuclei （AGN）. We explore the relation between the Doppler factors d of the jet of blazars and their broad line region luminosity LBLR. Since different methods measuring δ might differ substantially, we use data obtained from 3 independent methods and compile 3 samples of sources for each of them, respectively. Two samples consist of blazars, that is, Flat Spectrum Radio Quasars （FSRQs） and BL Lacertae objects （BL Lacs）, and the other consists of BL Lacs. dis one of the most important jet properties and LBLR is thought to be the proxy of the accretion power. Correlation analysis to these samples shows that there exists a significant correlation between δ and LBLR, which supports the idea that the jet powering process is closely linked with the accretion process and provides new evidence for disk-jet connection. Furthermore, the results are consistent with the idea that the Blandford-Znajek mechanism is sufficient for BL Lacs and a hybrid model is needed for FSRQs.
文摘[Objective] The aim was to summarize the characteristics of refelectivity factors of Doppler radar of the cold front cloud system. [Method] Judging from the characteristics of reflectivity factors, by dint of the new generation weather radar in Harbin from 2002 to 2007, the features of the reflectivity factors of the cold front cloud system were summarized. [Result] The cloud formed by the cold front was in banded form in general. However, there was void in the cloud and its intensity was uneven. Most fast moving cold front was long and narrow banded echo and basically the radial velocity turned from northwest wind to southwest. With the changes of month, the feature of the reflective rate also changed. In winter, the cold front cloud was in layer form. The feature of the reflectivity factors was weak and in large area. However, the structure was loose and there was space in the echo. Among them, there were several strong echoes. Strong convection cell echo formed in the two sides of the cold front, and it moved with the entire cloud belt. When the dry cold front moved, regional strong convective current formed, mainly by convective cloud and small echo area. Generally, the changes of the wind direction can not be expounded from the radial velocity. However, the intensity of the convection cell was distinct, 'three-body scattering', 'side lobe echo', and 'weak echo', as well as features of super convection cell. [Conclusion] The study provided positive role for the application of Doppler radar in the surveillance of weather in Heilongjiang Province.
文摘目的:本研究旨在探讨基于经颅多普勒超声(Transcranial doppler,TCD)与颈动脉超声评估急性缺血性卒中患者的预后影响因素。方法:选取2022年1月至2024年1月期间在本院诊断为急性缺血性卒中的患者120例作为研究对象。患者治疗后均随访6个月,并根据患者预后情况不同,将患者分为预后良好组和预后不良组。采用TCD和颈动脉超声收集患者的血流动力学指标及颈动脉病变参数。收集并对比患者的基线资料。通过Logistic回归分析评估急性缺血性卒中不良预后的影因素。结果:120例患者中,72例(60%)患者预后良好,48例(40%)患者预后不良。预后不良组的年龄明显大于预后良好组(P<0.05),但两组的性别、卒中病因及既往病史均无显著差异。预后良好组的中动脉峰值流速、中动脉平均流速均明显高于预后不良组,而颈动脉内膜-中层厚度、颈动脉狭窄率、不稳定斑块率、美国国立卫生研究院卒中量表(National Institutes of Health Stroke Scale,NIHSS)评分、血糖、总胆固醇(Total cholesterol,TC)、甘油三酯(Triglyceride,TG)、低密度脂蛋白胆固醇(Low density lipoprotein cholesterol,LDL-C)、C反应蛋白(C-reactive protein,CRP)水平均明显低于预后不良组(P<0.05)。Logistic回归分析显示,年龄、NIHSS评分、颈动脉狭窄率、中动脉峰值流速、不稳定斑块、血糖、TC、TG及CRP均是脑卒中不良预后的独立危险因素(P<0.05),中动脉平均流速及颈动脉内膜-中层厚度与不良预后无显著相关性。结论:TCD与颈动脉超声参数与急性缺血性卒中患者的预后相关,颈动脉狭窄率、中动脉峰值流速、不稳定斑块均是脑卒中不良预后的危险因素。
