[Objective] This study aimed to investigate the driving mechanism of eco- logical security in vulnerable areas in mountain and plain. [Method] The ecological security evaluation index system of Lincheng County was est...[Objective] This study aimed to investigate the driving mechanism of eco- logical security in vulnerable areas in mountain and plain. [Method] The ecological security evaluation index system of Lincheng County was established using PSR model. Driving mechanism was analyzed in total system and subsystems respectively by the principal components. The ecological safety driving factor was calculated through the total system and subsystem respectively. And the intersection was adopt- ed as dominant driving factor. [Result] A total of 10 indices including density index of rivers, land degradation index, farmland drought and flood insurance yield, human in- terference index, population density, the natural population growth rate, per capita GDP, the R＆D funds spending accounts for the proportion of GDP, laborer by edu- cation degree and three industry accounted for the proportion of GDP, are the domi- nant driving factors of the regional ecological security. [Conclusion] This study will pro- vide reasonable and feasible advice for the benign development of the area.展开更多
The significance of studying, monitoring and predicting blast induced vibration and noise level in mining and civil activities is justified in the capability of imposing damages, sense of uncertainty due to negative p...The significance of studying, monitoring and predicting blast induced vibration and noise level in mining and civil activities is justified in the capability of imposing damages, sense of uncertainty due to negative psychological impacts on involved personnel and also judicial complaints of local inhabitants in the nearby area. This paper presents achieved results during an investigation carried out at Sungun Copper Mine, lran. Besides, the research also studied the significance of blast induced ground vibration and air- blast on safety aspects of nearby structures, potential risks, frequency analysis, and human response. According to the United States Bureau of Mines （USBM） standard, the attenuation equations were devel- oped using field records. A general frequency analysis and risk evaluation revealed that： 94% of generated frequencies are less than 14 Hz which is within the natural frequency of structures that increases risk of damage. At the end, studies of human response showed destructive effects of the phenomena by ranging between 2.54 and 25.40 mm/s for ground vibrations and by the average value of 110 dB for noise levels which could increase sense of uncertainty among involved employees.展开更多
Hypertension is one of the well-established risk factor for cardiovascular diseases. Calcium channel blockers（CCBs）, chemicals that could block voltage-gated calcium channels（VGCCs） in cardiac muscle and blood ves...Hypertension is one of the well-established risk factor for cardiovascular diseases. Calcium channel blockers（CCBs）, chemicals that could block voltage-gated calcium channels（VGCCs） in cardiac muscle and blood vessels, has been widely used for the treatment of hypertension. Isradipine, a second-generation CCB with high affinity for voltage-operated calcium channels, has not been marked in China. The purpose of this study was to investigate the efficacy, safety and tolerability of isradipine in a phase I clinical trial including 31 healthy Chinese subjects. All subjects received different doses of isradipine at 2.5, 5.0 and 10.0 mg in single-dose study. When the test is completed, subjects treated with 5.0 mg isradipine stayed at the research center for multiple-dose study（5.0 mg isradipine twice daily for 9 d）. Systolic blood pressure（SBP） and diastolic blood pressure（DBP） were measured pre-dose and post-dose（1, 2, 4, 6, 8, 12, 24, 36 and 48 h after isradipine treatment）. Electrocardiography（ECG） and peripheral edema were monitored pre-dose and 4, 8, 24 and 48 h after isradipine treatment. SBP and DBP in single-dose study decreased after isradipine treatment. SBP reached the lowest values 8 h after dosing with a decrease of（7.0±9.7） mmHg（5.4%, P = 0.111） in 2.5 mg group,（7.0±6.9） mmHg（6.0%, P = 0.008） in 5.0 mg group, and（14.0±10.5） mmHg（12.7%, P = 0.005） for 10.0 mg group respectively. Similarly, DBP also reached the lowest values 8 h after dosing with a decrease of（10.0±7.9） mmHg（12.8%, P = 0.004） in 2.5 mg group,（6.0±7.0） mmHg（8.6%, P = 0.003） in 5.0 mg group, and（11.0±4.1） mmHg（15.1%, P = 0.000） in 10.0 mg group respectively. No significant changes of SBP and DBP were observed in multiple-dose study. We detected mild adverse events（AEs）, such as increased transaminase and headache that resolved rapidly and spontaneously without intervention. No serious or potentially life-threatening AE was detected. Our results indicate that isradipin has a good safety and tolerability in Chinese healthy subjects. Long-term study with larger sample size is needed to confirm our conclusion.展开更多
基金Supported by Hebei Provincial Natural Science Fund for Youth (D2010001566)Projects of Hebei Academy of Science and Technology (12116, 13140)Hebei Key Technology Research and Development Program (11237126D)~~
文摘[Objective] This study aimed to investigate the driving mechanism of eco- logical security in vulnerable areas in mountain and plain. [Method] The ecological security evaluation index system of Lincheng County was established using PSR model. Driving mechanism was analyzed in total system and subsystems respectively by the principal components. The ecological safety driving factor was calculated through the total system and subsystem respectively. And the intersection was adopt- ed as dominant driving factor. [Result] A total of 10 indices including density index of rivers, land degradation index, farmland drought and flood insurance yield, human in- terference index, population density, the natural population growth rate, per capita GDP, the R＆D funds spending accounts for the proportion of GDP, laborer by edu- cation degree and three industry accounted for the proportion of GDP, are the domi- nant driving factors of the regional ecological security. [Conclusion] This study will pro- vide reasonable and feasible advice for the benign development of the area.
文摘The significance of studying, monitoring and predicting blast induced vibration and noise level in mining and civil activities is justified in the capability of imposing damages, sense of uncertainty due to negative psychological impacts on involved personnel and also judicial complaints of local inhabitants in the nearby area. This paper presents achieved results during an investigation carried out at Sungun Copper Mine, lran. Besides, the research also studied the significance of blast induced ground vibration and air- blast on safety aspects of nearby structures, potential risks, frequency analysis, and human response. According to the United States Bureau of Mines （USBM） standard, the attenuation equations were devel- oped using field records. A general frequency analysis and risk evaluation revealed that： 94% of generated frequencies are less than 14 Hz which is within the natural frequency of structures that increases risk of damage. At the end, studies of human response showed destructive effects of the phenomena by ranging between 2.54 and 25.40 mm/s for ground vibrations and by the average value of 110 dB for noise levels which could increase sense of uncertainty among involved employees.
文摘Hypertension is one of the well-established risk factor for cardiovascular diseases. Calcium channel blockers（CCBs）, chemicals that could block voltage-gated calcium channels（VGCCs） in cardiac muscle and blood vessels, has been widely used for the treatment of hypertension. Isradipine, a second-generation CCB with high affinity for voltage-operated calcium channels, has not been marked in China. The purpose of this study was to investigate the efficacy, safety and tolerability of isradipine in a phase I clinical trial including 31 healthy Chinese subjects. All subjects received different doses of isradipine at 2.5, 5.0 and 10.0 mg in single-dose study. When the test is completed, subjects treated with 5.0 mg isradipine stayed at the research center for multiple-dose study（5.0 mg isradipine twice daily for 9 d）. Systolic blood pressure（SBP） and diastolic blood pressure（DBP） were measured pre-dose and post-dose（1, 2, 4, 6, 8, 12, 24, 36 and 48 h after isradipine treatment）. Electrocardiography（ECG） and peripheral edema were monitored pre-dose and 4, 8, 24 and 48 h after isradipine treatment. SBP and DBP in single-dose study decreased after isradipine treatment. SBP reached the lowest values 8 h after dosing with a decrease of（7.0±9.7） mmHg（5.4%, P = 0.111） in 2.5 mg group,（7.0±6.9） mmHg（6.0%, P = 0.008） in 5.0 mg group, and（14.0±10.5） mmHg（12.7%, P = 0.005） for 10.0 mg group respectively. Similarly, DBP also reached the lowest values 8 h after dosing with a decrease of（10.0±7.9） mmHg（12.8%, P = 0.004） in 2.5 mg group,（6.0±7.0） mmHg（8.6%, P = 0.003） in 5.0 mg group, and（11.0±4.1） mmHg（15.1%, P = 0.000） in 10.0 mg group respectively. No significant changes of SBP and DBP were observed in multiple-dose study. We detected mild adverse events（AEs）, such as increased transaminase and headache that resolved rapidly and spontaneously without intervention. No serious or potentially life-threatening AE was detected. Our results indicate that isradipin has a good safety and tolerability in Chinese healthy subjects. Long-term study with larger sample size is needed to confirm our conclusion.
