Analysis of Lightning Disaster in Shaoyang City and Research on Its Defense Countermeasures

The climate impact assessment and monthly and annual reports of surface meteorological observation of cities and counties were reviewed,and there were no records of lightning disasters in Shaoyang from 1978 to 2000.Since 2001,there have been few records of lightning disasters,with only about 10 times in various regions.In this paper,a total of 143 investigation reports on lightning accidents since 2002 were collected,and statistical analysis was conducted based on the loss,location of occurrence,damaged industries,and social impact.In particular,the temporal and spatial distribution characteristics of lightning in Shaoyang area have been clearly understood,and the main characteristics and laws of lightning accidents in Shaoyang area were revealed.The results showed that the most lightning accidents occurred in June,and no lightning accidents occurred in December.Dongkou,Longhui,and Shaoyang urban areas were the lightning prone areas,and the impact of lightning on agriculture was the largest,followed by commerce.The prevention countermeasures of lightning disasters were proposed to provide reference for disaster prevention and reduction.

Primary Screening for Breast Diseases among 17618 Women in Wufeng Area, a Region with High Incidence of Cervical Cancer in China

In this study, the current status for breast diseases in a region with high-incidence of cervical cancer were epidemiologically investigated. From March to August, 2009, 17618 women, from Wufeng area of Hubei province, China, were recruited to screen breast diseases by using breast infrared diagnostic apparatus. Other diagnostic methods, such as B-mode ultrasound, X-ray mammography, needle biopsy and pathological examination were, if necessary, used to further confirm the diagnosis. The screening showed that 5990 of 17618 cases (34.00%) had breast diseases, 5843 (33.16%) had mammary gland hyperplasia, 48 (0.27%) had breast fibroadenoma, 11 (0.06%) had breast carcinoma, and 88 (0.50%) had other breast diseases. The peak morbidity of breast cancer was found in the women aged 50–60 ages. The morbidity of breast cancer was significantly increased in women elder than or equal to 50 years old (n=8, 0.157%) in comparison with that in the subjects younger than 50 years old (n=3, 0.024%) (u=2.327, P<0.05). It was shown that the occurrence of breast diseases was concentrated in women aged 20–40 years, while the total morbidity reached its peak at the age of 30 years and then decreased sharply after age of 40. Compared with the patients elder than or equal to 40 years old (n=3289, 27.46%), the morbidity rate of breast diseases was significantly increased in women less than 40 years old (2648 cases, 47.18%; P<0.001). However, there was no significant difference in the morbidity of breast diseases between the age group of 20–29 years and that of 30–39 years (P=0.453), and both of them were high. There was no significant association between the morbidity of breast diseases and cervical cancer. Since the morbidity of breast diseases was higher among young women, more attention should be paid to the screening of breast diseases among young women for early diagnosis.

Influence of nose-perturbation location on behavior of vortical flow around slender body at high incidence

Response of the vortical flow around a slender body of revolution at high incidence to the shift of a single nose perturbation was investigated systematically using numerical methods. A minute geometric bump was employed to act as the nose perturbation, and all computations were performed for subsonic flows at incidence of 50°. The computational results show that the vortical flow is more sensitive to the perturbation located axially closer to the nose apex of a slender body. With perturbation shifting axially downstream away from nose apex, there is a critical axial location appearing. The vortical flow is less sensitive to the perturbation located axially closer to the critical axial location; when perturbation traverses axially around the critical axial location, the vortical flow switches between opposite asymmetric patterns. The eventual influence of perturbation axial location on the vortical flow lies on both its relative locations to nose apex and the critical axial location. The vortical flow is more sensitive to the perturbation located circumferentially farther away from the fore-and-aft symmetric plane of a slender body, and just the asymmetrically-located perturbation can provoke the vortical flow to asymmetry. With perturbation shifting circumferentially in sequence, the vortical flow varies by degrees in manner of a single periodicity. A convective-type of instability existing in the flow field is responsible for the influence of nose perturbation on the vortical flow.