Clean syngas from biomass—process development and concept assessment

This paper summarises the long development work done at VTT for gas clean-up for various synthesis applications. The development work has covered the most challenging and costly steps in biomass gasification based processes: high-temperature gas filtration and reforming of hydrocarbon gases and tars. The tar content of product gas is one of the main factors defining the temperature window in which the hot-gas filter can be operated, which in the case of fluidized-bed gasification is at 350-500 °C. Research is ongoing to achieve higher and thus more economical operation temperatures. Optimal operation of a catalytic reformer can be achieved by using a staged reformer where zirconia-based catalysts are used as a pre-reformer layer before nickel and/or precious metal-based catalyst stages. The temperature of the reformer is optimally increased in subsequent stages from 600 up to 1,000 °C. According to the techno-economic analysis, increasing the hot-gas filtration temperature by 300 °C or methane conversion in the reformer from 55 to 95 % both lead to about 5 % reduction the liquid fuel production cos

Cysticercosis in experimentally and naturally infected pigs: parasitological and immunological diagnosis

Our objective was to evaluate the diagnosis of swine cysticercosis by examining "ante mortem" (inspection of the tongue), "post mortem" (inspection and detailed necropsy) and ELISA for research in serum of antibodies (Ab-ELISA) and antigens (Ag-ELISA). Seven (7) pigs were experimentally infected orally with eggs of Taenia solium and another 10 were naturally infected. In the pigs experimentally infected, inspection of the tongue was negative in all animals, in the routine inspection detailed necropsy and cysticercis were identified in all of them. In pigs with heavy natural infection, inspection of the tongue identified cysticerci in two (20%), while at inspection with necropsy the parasites were identified in large quantities in all animals. In ELISA for antibody search (Ab-ELISA) TS-14 recombinant protein was used, and in search for antigen (Ag-ELISA) a monoclonal antibody against this protein. In animals experimentally infected, blood was collected weekly for 140 days. The Ab-ELISA identified an increase in titers of antibody to cysticerci 21 days after infection, and at the end of the experimental period six animals (86%) were positive to the test. The search for circulating antigens (Ag-ELISA) was positive in two pigs 28 to 91 days after infection. All naturally infected pigs were positive for Ag-ELISA and Ab-ELISA. The search for antibodies and antigens by ELISA in serum from 30 pigs of a local farm and without history of cysticercosis was negative. Thus, the use of TS-14 antigen in ELISA test (Ab-ELISA) can be useful for the diagnosis of cysticercosis in pigs with low infection

Cysticercus Antigens in Cerebrospinal Fluid Samples from Patients with Neurocysticercosis

Antigens were detected in cerebrospinal fluid (CSF) samples from patients with neurocysticercosis (NC) by enzyme-linked immunosorbent assay (ELISA) using polyclonal sera of rabbit anti-Taenia solium cysticerci (anti-Tso) and anti- Taenia crassiceps cysticerci vesicular fluid (anti-Tcra or anti-Tcra <30 kDa). A group of NC patients (n = 174) were studied (NC), including 40 patients in different phases of the disease. ELISAs carried out with the anti-Tso, anti-Tcra, and anti-Tcra <30 kDa showed sensitivities of 81.2, 90, and 95.8% and specificities of 82, 98, and 100%, respectively. The 14- and 18-kDa low-molecular-weight peptides were only detected in CSF samples from patients with NC by immunoblotting with anti-Tso and anti-Tcra sera. Because of the importance of the diagnosis and prognosis of cysticercosis, the detection of antigens may contribute as an additional marker to the study and clarification of the parasite-host relationship