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51.
The hepatitis E virus (HEV) is the causative agent of Hepatitis E, an enterically transmitted disease. HEV infections in pigs and humans have been reported worldwide, but data from Mexico are scarce. In the present study, the prevalence of anti-HEV IgG antibodies was investigated in a quite large number of swine from Mexico by means of an ELISA based on a recombinant open reading frame 2 protein of HEV genotype 3. Serum samples from 683 healthy pigs (1–48 months old), collected during 2010–2013 in 109 herds from 48 municipalities located in 9 states in the centre of the country were assayed. A 30.75 % (210/683) of the sera tested were positive, and they were distributed along all the states included in the study. The prevalence of anti-HEV antibodies varied widely between municipalities and herds, and it was higher in pigs 4–6 months of age. No relationships were detected between seroprevalences and farm characteristics. Forty individual faecal samples were analysed by RT-PCR and all resulted negative. These data indicate that HEV infection is widespread in Mexican pigs; thus, representing a potential zoonotic risk for humans.  相似文献   
52.
New renewable fuels are urgently needed due to increasing fossil fuel pollution. Biodiesel, which contains alkyl esters produced by transesterification of oils, is an alternative fuel. Nevertheless, the main problem of biodiesel is its high price. Costs can be reduced by replacement of the current homogeneous catalysts by heterogeneous catalysts; however, research for new catalysts is actually slowed by lengthy analytical techniques. Here, we set up a simple and rapid analytical method using Fourier transform infrared (FTIR) to monitor transesterification. Conversion of sunflower and recycled cooking oils to their corresponding methyl esters was easily measured using a linear correlation between the intensity of an infrared peak at 1,437 cm?1 and the percent conversion. The results obtained by infrared were validated by gas chromatography. We also studied the effect of 20 kHz ultrasonic irradiation on biodiesel synthesis. Using our FTIR method, we found that replacing mechanical stirring with an ultrasonic probe leads to quality biodiesel in 10 min for sunflower oil and 20 min for recycled cooking oil.  相似文献   
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