地面沉降是许多城市面临的一种持续时间长、影响范围广的地质灾害。北京平原区的地面沉降发现早、监测时序长,分析其时空演化特征可以为地面沉降的防控提供重要的数据支撑。时空主成分分析ST-PCA(Spatial and Temporal Principal Compon...地面沉降是许多城市面临的一种持续时间长、影响范围广的地质灾害。北京平原区的地面沉降发现早、监测时序长,分析其时空演化特征可以为地面沉降的防控提供重要的数据支撑。时空主成分分析ST-PCA(Spatial and Temporal Principal Component Analysis)是将一组互为相关的变量转化为另一组新的不相关的变量的数学变换方法,在地学领域用于提取时空数据在时间和空间维度的动态演化特征。本研究利用永久散射体合成孔径雷达干涉测量PS-InSAR(Persistent Scatterer Interferometric Synthetic Aperture Radar)技术获得北京平原区2010—2016年长时序的地面沉降数据的基础上,采用ST-PCA方法揭示北京平原区地面沉降的趋势特征、波动特征,相应的空间分布模式及其时序演化规律。结果表明:(1)时间主成分分析方法TPCA(Temporal Principal Component Analysis)的第一主成分TPC1分析发现北京平原区整体呈现为空间分布不均匀沉降的特点;第二主成分TPC2分析发现在沉降速率>30 mm/a的沉降漏斗区呈明显的、南北分化的季节性差异空间分布特征,表现为北部地区夏季沉降量较大,南部地区冬季沉降量较大。(2)空间主成分分析SPCA(Spatial Principal Component Analysis)的第一主成分SPC1分析发现大部分地区具有沉降为主的特征,地面沉降呈持续的、线性下降的趋势;第二主成分SPC2和第三主成分SPC3分析则发现在轻微沉降区和非沉降区年均沉降量接近于0 mm/a,但是季节性波动特征明显。总之,北京平原区地面沉降在时间上呈持续性线性趋势与季节性波动相结合特征,空间上表现为分布不均匀与区域集聚特征,沉降漏斗区则更表现有时空叠加效应。展开更多
Introduction: This study aimed to compare the frequency of diabetic and non-diabetic patients admitted for ST-elevation myocardial infarction (STEMI), assess their epidemiological, clinical, and paraclinical profiles,...Introduction: This study aimed to compare the frequency of diabetic and non-diabetic patients admitted for ST-elevation myocardial infarction (STEMI), assess their epidemiological, clinical, and paraclinical profiles, and evaluate their therapeutic strategies and outcomes. Methodology: A descriptive, analytical, comparative study with prospective and retrospective data collection was conducted from April 1, 2020, to March 31, 2021. Diabetic and non-diabetic patients with STEMI admitted to a cardiology department were included. STEMI diagnosis was based on clinical and electrocardiographic criteria showing persistent ST-segment elevation in at least two leads. All patients included in the study signed a written, informed consent form. Data analysis was performed using SPSS, with a p-value ≤ 0.05 considered statistically significant. Results: STEMI prevalence was 15.27%, with 37.11% of patients being diabetic and 62.89% non-diabetic. Diabetic patients had a mean age of 59.2 ± 10.9 years, while non-diabetics averaged 58 ± 13.4 years. Diabetics were predominantly female (72.2%), whereas non-diabetics were mainly male (83.6%). Smoking was less frequent among diabetics (25% vs. 47.54%), but hypertension, obesity, and sedentary lifestyle were more common. Diabetics had an average of 3.5 ± 1.1 risk factors compared to 2.6 ± 1.2 in non-diabetics. Admission delay was longer for diabetics (34.8 ± 51.6 hours vs. 23.3 ± 52.3 hours). Chest pain was the main symptom in both groups. Electrocardiograms showed that anterior and inferior infarctions were most frequent. Triple vessel disease and severe complications, such as cardiogenic shock, were more common in diabetics, who also had higher mortality (5.56% vs. 3.28%). Conclusion: Diabetic STEMI patients represent a high-risk group with distinct clinical features, longer admission delays, and a greater accumulation of cardiovascular risk factors, emphasizing the need for targeted interventions.展开更多
文摘地面沉降是许多城市面临的一种持续时间长、影响范围广的地质灾害。北京平原区的地面沉降发现早、监测时序长,分析其时空演化特征可以为地面沉降的防控提供重要的数据支撑。时空主成分分析ST-PCA(Spatial and Temporal Principal Component Analysis)是将一组互为相关的变量转化为另一组新的不相关的变量的数学变换方法,在地学领域用于提取时空数据在时间和空间维度的动态演化特征。本研究利用永久散射体合成孔径雷达干涉测量PS-InSAR(Persistent Scatterer Interferometric Synthetic Aperture Radar)技术获得北京平原区2010—2016年长时序的地面沉降数据的基础上,采用ST-PCA方法揭示北京平原区地面沉降的趋势特征、波动特征,相应的空间分布模式及其时序演化规律。结果表明:(1)时间主成分分析方法TPCA(Temporal Principal Component Analysis)的第一主成分TPC1分析发现北京平原区整体呈现为空间分布不均匀沉降的特点;第二主成分TPC2分析发现在沉降速率>30 mm/a的沉降漏斗区呈明显的、南北分化的季节性差异空间分布特征,表现为北部地区夏季沉降量较大,南部地区冬季沉降量较大。(2)空间主成分分析SPCA(Spatial Principal Component Analysis)的第一主成分SPC1分析发现大部分地区具有沉降为主的特征,地面沉降呈持续的、线性下降的趋势;第二主成分SPC2和第三主成分SPC3分析则发现在轻微沉降区和非沉降区年均沉降量接近于0 mm/a,但是季节性波动特征明显。总之,北京平原区地面沉降在时间上呈持续性线性趋势与季节性波动相结合特征,空间上表现为分布不均匀与区域集聚特征,沉降漏斗区则更表现有时空叠加效应。
基金supported by National Science Foundation of China(11001226)Youth Foundation of Department of Education of Sichuan Province(11ZB174)+2 种基金Special Foundation from Department of Land and Resources of Shanxi Province(2009SXGTKY06)supported by Research Fund of Chengdu University of Information Technology(KYTZ201003)Qing Lan Project of Jiangsu Province~~
文摘Introduction: This study aimed to compare the frequency of diabetic and non-diabetic patients admitted for ST-elevation myocardial infarction (STEMI), assess their epidemiological, clinical, and paraclinical profiles, and evaluate their therapeutic strategies and outcomes. Methodology: A descriptive, analytical, comparative study with prospective and retrospective data collection was conducted from April 1, 2020, to March 31, 2021. Diabetic and non-diabetic patients with STEMI admitted to a cardiology department were included. STEMI diagnosis was based on clinical and electrocardiographic criteria showing persistent ST-segment elevation in at least two leads. All patients included in the study signed a written, informed consent form. Data analysis was performed using SPSS, with a p-value ≤ 0.05 considered statistically significant. Results: STEMI prevalence was 15.27%, with 37.11% of patients being diabetic and 62.89% non-diabetic. Diabetic patients had a mean age of 59.2 ± 10.9 years, while non-diabetics averaged 58 ± 13.4 years. Diabetics were predominantly female (72.2%), whereas non-diabetics were mainly male (83.6%). Smoking was less frequent among diabetics (25% vs. 47.54%), but hypertension, obesity, and sedentary lifestyle were more common. Diabetics had an average of 3.5 ± 1.1 risk factors compared to 2.6 ± 1.2 in non-diabetics. Admission delay was longer for diabetics (34.8 ± 51.6 hours vs. 23.3 ± 52.3 hours). Chest pain was the main symptom in both groups. Electrocardiograms showed that anterior and inferior infarctions were most frequent. Triple vessel disease and severe complications, such as cardiogenic shock, were more common in diabetics, who also had higher mortality (5.56% vs. 3.28%). Conclusion: Diabetic STEMI patients represent a high-risk group with distinct clinical features, longer admission delays, and a greater accumulation of cardiovascular risk factors, emphasizing the need for targeted interventions.
