Risk factors for Enterobius vermicularis infection in children in Gaozhou, Guangdong, China

Background:Enterobius vermicularis infection is a prevalent intestinal parasitic disease in children.In this study,we explored the epidemiological status and risk factors for E.vermicularis infection in children in southern China.Methods:A cross-sectional survey was carried out in Gaozhou city,Guangdong province,China,in December 2011.Children aged 2–12 years from five schools participated in the study.The adhesive cellophane-tape perianal swab method was applied to detect E.vermicularis infection,while a questionnaire was sent to each child’s guardian(s)to collect demographic and socioeconomic data,as well as hygiene behaviors,pertaining to each child.Univariate and multivariate logistic regression analyses were performed to capture the potential risk factors.Results:Out of the 802 children surveyed,440 were infected with E.vermicularis,with an average prevalence of 54.86%,and a range from 45.96 to 68.13%.The age variable was found to be statistically significant,whereas the sex variable was not.It was found that a mother’s education level(low)and not washing hands before dinner were major risk factors in all children(802).After stratification by age,a father’s education level(primary or below)and biting pencils(or toys)were significant risk factors in the younger children(508),while not washing hands before dinner and playing on the ground were important risk factors in the older children(294).Conclusion:This study demonstrates the prevalence of E.vermicularis infection in children in Gaozhou and reveals underlying risk factors.Most importantly,it reveals that risk factors differ among the different age groups,which indicates that different control measures targeted at particular age groups should be implemented.

A trapezoidal cantilever density sensor based on MEMS technology

A trapezoidal cantilever density sensor is developed based on micro-electro-mechanical systems （MEMS） technology. The sensor measures fluid density through the relationship between the density and the resonant frequency of the cantilever im-mersed in the fluid. To improve the sensitivity of the sensor, the modal and harmonic response analyses of trapezoidal and rec-tangular cantilevers are simulated by ANSYS software. The higher the resonant frequency of the cantilever immersed in the fluid, the higher the sensitivity of the sensor; the higher the resonant strain value, the easier the detection of the output signal of the sensor. Based on the results of simulation, the trapezoidal cantilever is selected to measure the densities of dimethyl silicone and toluene at the temperature ranges of 30 to 55 ℃ and 26 cantilever density sensor has a good performance. to 34 ℃, respectively. Experimental results show that the trapezoidal cantilever density sensor has a good pertbrmance.