This paper presents an empirical analysis of the epidemiological data concerning the 18445 HFMD-infected cases in Beijing in 2008. The main findings are as follows. (i) Seasonal variations in incidence were observed, with a peak observed during the summer season, especially in May. Male patients outnumber female patients by 1.57 : 1. (ii) Most cases occurred in children 4 years old or younger. Outperforming Weibull distribution and Gamma distribution as to model fitness when analyzing patient ages, log-normal distribution indicates that the estimated mean age is 3.4 years. (iii) The age distribution seems to indicate cyclic peaks with roughly one-year intervals. (iv) Correlation analyses (ρ = 0.9864) show that time of birth in different months has an impact on the chance of being infected by HFMD. Birth month seems to present a high risk factor on infants and young children.(v) The morbidity rate is 132.7/100000 during the HFMD epidemic in Beijing in 2008. The morbidity map shows that the risks of HFMD infection in areas close to the city center and suburbans are much lower than those in the urban-rural transition zones. Spatial risks inferred from the morbidity map demonstrate a clear circular pattern. (vi) The prevention and control measures taken by the public health departments seem to be effective during the summer season, resulting in the early ending of the epidemic (one month earlier than the natural season) and reduced outbreak size.Hand-Foot-Mouth disease, epidemiological analysis, spread mechanism, risk factor, morbidity map, Beijing Citation:

Vibration is an omnipresent energy source that is renewable and has the potential to cause damage to transmission lines. Harvesting harmful vibration energy can achieve vibration attenuation. Here, a vibration-driven triboelectric nanogenerator (V-TENG) with the potential for vibration attenuation is proposed as a power source for monitoring the operating condition of transmission lines. The V-TENG with structural optimization and frequency response range improvement is first discussed, indicating that it has a simple structural design with a good output performance. Then an energy management circuit is used to improve the charging efficiency of large capacitors. The vibration attenuation effect and wireless transmission system are verified in the simulation environment, benefiting from the welldesigned structure and outstanding electric performance. This work demonstrates an efficient strategy for harvesting vibration energy through the TENG, which provides valuable guidance for further construction of online monitoring of transmission lines.

Studying spatio-temporal evolution of epidemics can uncover important aspects of interaction among people, infectious diseases, and the environment, providing useful insights and modeling support to facilitate public health response and possibly prevention measures. This paper presents an empirical spatio-temporal analysis of epidemiological data concerning 2321 SARS-infected patients in Beijing in 2003. We mapped the SARS morbidity data with the spatial data resolution at the level of street and township. Two smoothing methods, Bayesian adjustment and spatial smoothing, were applied to identify the spatial risks and spatial transmission trends. Furthermore, we explored various spatial patterns and spatio-temporal evolution of Beijing 2003 SARS epidemic using spatial statistics such as Moran's I and LISA. Part of this study is targeted at evaluating the effectiveness of public health control measures implemented during the SARS epidemic. The main findings are as follows. (1) The diffusion speed of SARS in the northwest-southeast direction is weaker than that in northeast-southwest direction. (2) SARS's spread risk is positively spatially associated and the strength of this spatial association has experienced changes from weak to strong and then back to weak during the lifetime of the Beijing SARS epidemic. (3) Two spatial clusters of disease cases are identified: one in the city center and the other in the eastern suburban area. These two clusters followed different evolutionary paths but interacted with each other as well. (4) Although the government missed the opportunity to contain the early outbreak of SARS in March 2003, the response strategies implemented after the mid of April were effective. These response measures not only controlled the growth of the disease cases, but also mitigated the spatial diffusion. Severe acute respiratory syndrome (SARS) is a respiratory disease with a high case-fatality rate, which is thought to be transmitted primarily by close person-to-person contact. Transmission occurs through respiratory droplets produced when an infected person sneezes and/or by touching a surface or object contaminated with infectious droplets. Many natural and social-economic factors contributed to and influenced SARS transmissions. To gain a better understanding of the SARS transmission mechanism and help design and assess related public health response and control measures, public health researchers and practitioners need to carefully and systematically study spatial and temporal evolution of SARS cases, identify risk factors, and evaluate the specific impact of control measures implemented. The 2003 SARS outbreaks represented one of the most serious public health challenges to China and the world.