The optimal evacuation scheme is studied based on the dam-break flood numerical simulation. A three- dimensional dam-break mathematical model combined with the volume of fluid (VOF) method is adopted. According to t...The optimal evacuation scheme is studied based on the dam-break flood numerical simulation. A three- dimensional dam-break mathematical model combined with the volume of fluid (VOF) method is adopted. According to the hydraulic information obtained from numerical simulation and selecting principles of evacuation emergency scheme, evacuation route analysis model is proposed, which consists of the road right model and random degree model. The road right model is used to calculate the consumption time in roads, and the random degree model is used to judge whether the roads are blocked. Then the shortest evacuation route is obtained based on Dijstra algorithm. Gongming Reservoir located in Shenzhen is taken as a case to study. The results show that industrial area I is flooded at 2 500 s, and after 5 500 s, most of industrial area II is submerged. The Hushan, Loucun Forest and Chaishan are not flooded around industrial area I and II. Based on the above analysis, the optimal evacuation scheme is determined.展开更多
Due to frequent drinking water pollution accidents in the past decade, it is common that mountain reservoirs were used as the source of drinking water in China. However, some coastal areas frequently suffer from typho...Due to frequent drinking water pollution accidents in the past decade, it is common that mountain reservoirs were used as the source of drinking water in China. However, some coastal areas frequently suffer from typhoon with extreme precipitation, which results in the water quality deterioration of the reservoirs. The influence of typhoons with extreme precipitation on Jiaokou reservoir and the emergency treatment process of Maojiaping water treatment plant in the past three typical typhoons with extreme precipitation from the year of 2012-2015 were studied. It was found that the degradation of water quality, such as the increase of turbidity and bacteria index, may not merely appear during the events, but last for several days. Changing the dosage of water purification agent, such as coagulant and disinfectant at right time and place may be an efficient emergency water treatment process. Based on the analysis of water quality variation rule during and after the events, it was also found that emergency treatment can be fully prepared before the arrival of a typhoon with extreme precipitation. And in order to better respond to the typhoon with extreme precipitation, several suggestions are also proposed in this paper as follows: establishing vegetated buffers at right place, such as macrophanerophytes,shrub or herbage, increasing investments in infrastructure management, merging or cancelling the small-scale water treatment plants, preparing adequate water purification agent before the typhoon comes, etc.展开更多
AIM: To determine the and clinical features of prevalence, histologic types primary epithelial tumours of the vermiform appendix in a predominantly black population.METHODS: All cases of primary tumours of the appen...AIM: To determine the and clinical features of prevalence, histologic types primary epithelial tumours of the vermiform appendix in a predominantly black population.METHODS: All cases of primary tumours of the appendix identified by review of the histopathology records at the University of the West Indies between January 1987 and June 2007 were selected. Relevant pathologic and clinical data were extracted with supplementation from patient charts where available. Non-epithelial tumours were excluded. The total number of appendectomy specimens over the period was also ascertained.RESULTS: Forty-two primary epithelial tumours were identified out of 6 824 appendectomies yielding a prevalence rate of approximately 0.62%. Welldifferentiated neuroendocrine cell tumours (carcinoids, 47.6%) and benign non-endocrine cell tumours (adenomas, 45.2%) were most common with nearly equal frequency. The median age was 43 years, with no sex predilection. Carcinoid tumours occurred in younger patients (mean age 32 years), with a male-to-female ratio of 1.2:1. A clinical diagnosis of acute appendicitis was the most common reason for appendectomy (57.1%) and was histologically confirmed in 75% (18 of 24) of cases. In total, 16.7% of cases were diagnosed after incidental appendectomy.CONCLUSION: Appendiceal epithelial tumours are rare in our experience, and are represented principally by carcinoid turnours and adenornas. Carcinoid tumours occurred in younger patients but were slightly more common in men than women. Tumours were not suspected clinically and were diagnosed incidentally in specimens submitted for acute appendicitis supporting the need for histological evaluation in all resection specimens.展开更多
This paper gives a brief introduction to the emergency handling of Tangjiashan barrier lake.Some technologies for the application of geological and topographical data are summarized and the mechanism of formation of a...This paper gives a brief introduction to the emergency handling of Tangjiashan barrier lake.Some technologies for the application of geological and topographical data are summarized and the mechanism of formation of a barrier lake is analyzed.Based on the safety status evaluation,the dam breach flood point is calculated.The paper concludes with discussion of the practical effects of emergency handling scenarios and different drainage channel designs.展开更多
False aneurysm of the femoral artery is a rare complication of intertrochanteric fracture. Most of these situations are due to iatrogenic trauma or the trauma itself and are rarely caused by dislocated bone fragments....False aneurysm of the femoral artery is a rare complication of intertrochanteric fracture. Most of these situations are due to iatrogenic trauma or the trauma itself and are rarely caused by dislocated bone fragments. Here we report a case of a 72-year-old man who presented acutely with a pseudoaneurysm of the superficial femoral artery from the spike of a lesser trochanter fragment. Percutaneous endovascular treatment of the pseudoaneurysm with a covered stent was undertaken on an urgent basis. Five days later, the patient was operated upon and the lesser trochanter fragment was excised through an anterior incision and the intertrochanteric fracture was fixed using dynamic hip screws. The fracture was united at 10 weeks. At one-year's follow-up, there were no graft-related complications. This case illustrates that an intertrochanteric fracture with a dis- placed lesser trochanter fragment can present acutely with bleeding and a pseudoaneurysm of the femoral artery.展开更多
基金Supported by Natural Science Foundation of Tianjin (No.09JCYBJC08700)the Foundation for Innovative Research Groups of National Natural Science Foundation of China (No.51021004)National Natural Science Foundation of China (No.90815019)
文摘The optimal evacuation scheme is studied based on the dam-break flood numerical simulation. A three- dimensional dam-break mathematical model combined with the volume of fluid (VOF) method is adopted. According to the hydraulic information obtained from numerical simulation and selecting principles of evacuation emergency scheme, evacuation route analysis model is proposed, which consists of the road right model and random degree model. The road right model is used to calculate the consumption time in roads, and the random degree model is used to judge whether the roads are blocked. Then the shortest evacuation route is obtained based on Dijstra algorithm. Gongming Reservoir located in Shenzhen is taken as a case to study. The results show that industrial area I is flooded at 2 500 s, and after 5 500 s, most of industrial area II is submerged. The Hushan, Loucun Forest and Chaishan are not flooded around industrial area I and II. Based on the above analysis, the optimal evacuation scheme is determined.
基金supported by the National Science Foundation of China(NSFC)(grant number 51438006)Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Due to frequent drinking water pollution accidents in the past decade, it is common that mountain reservoirs were used as the source of drinking water in China. However, some coastal areas frequently suffer from typhoon with extreme precipitation, which results in the water quality deterioration of the reservoirs. The influence of typhoons with extreme precipitation on Jiaokou reservoir and the emergency treatment process of Maojiaping water treatment plant in the past three typical typhoons with extreme precipitation from the year of 2012-2015 were studied. It was found that the degradation of water quality, such as the increase of turbidity and bacteria index, may not merely appear during the events, but last for several days. Changing the dosage of water purification agent, such as coagulant and disinfectant at right time and place may be an efficient emergency water treatment process. Based on the analysis of water quality variation rule during and after the events, it was also found that emergency treatment can be fully prepared before the arrival of a typhoon with extreme precipitation. And in order to better respond to the typhoon with extreme precipitation, several suggestions are also proposed in this paper as follows: establishing vegetated buffers at right place, such as macrophanerophytes,shrub or herbage, increasing investments in infrastructure management, merging or cancelling the small-scale water treatment plants, preparing adequate water purification agent before the typhoon comes, etc.
文摘AIM: To determine the and clinical features of prevalence, histologic types primary epithelial tumours of the vermiform appendix in a predominantly black population.METHODS: All cases of primary tumours of the appendix identified by review of the histopathology records at the University of the West Indies between January 1987 and June 2007 were selected. Relevant pathologic and clinical data were extracted with supplementation from patient charts where available. Non-epithelial tumours were excluded. The total number of appendectomy specimens over the period was also ascertained.RESULTS: Forty-two primary epithelial tumours were identified out of 6 824 appendectomies yielding a prevalence rate of approximately 0.62%. Welldifferentiated neuroendocrine cell tumours (carcinoids, 47.6%) and benign non-endocrine cell tumours (adenomas, 45.2%) were most common with nearly equal frequency. The median age was 43 years, with no sex predilection. Carcinoid tumours occurred in younger patients (mean age 32 years), with a male-to-female ratio of 1.2:1. A clinical diagnosis of acute appendicitis was the most common reason for appendectomy (57.1%) and was histologically confirmed in 75% (18 of 24) of cases. In total, 16.7% of cases were diagnosed after incidental appendectomy.CONCLUSION: Appendiceal epithelial tumours are rare in our experience, and are represented principally by carcinoid turnours and adenornas. Carcinoid tumours occurred in younger patients but were slightly more common in men than women. Tumours were not suspected clinically and were diagnosed incidentally in specimens submitted for acute appendicitis supporting the need for histological evaluation in all resection specimens.
文摘This paper gives a brief introduction to the emergency handling of Tangjiashan barrier lake.Some technologies for the application of geological and topographical data are summarized and the mechanism of formation of a barrier lake is analyzed.Based on the safety status evaluation,the dam breach flood point is calculated.The paper concludes with discussion of the practical effects of emergency handling scenarios and different drainage channel designs.
文摘False aneurysm of the femoral artery is a rare complication of intertrochanteric fracture. Most of these situations are due to iatrogenic trauma or the trauma itself and are rarely caused by dislocated bone fragments. Here we report a case of a 72-year-old man who presented acutely with a pseudoaneurysm of the superficial femoral artery from the spike of a lesser trochanter fragment. Percutaneous endovascular treatment of the pseudoaneurysm with a covered stent was undertaken on an urgent basis. Five days later, the patient was operated upon and the lesser trochanter fragment was excised through an anterior incision and the intertrochanteric fracture was fixed using dynamic hip screws. The fracture was united at 10 weeks. At one-year's follow-up, there were no graft-related complications. This case illustrates that an intertrochanteric fracture with a dis- placed lesser trochanter fragment can present acutely with bleeding and a pseudoaneurysm of the femoral artery.