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This study investigated the use of ceramic membranes to remove total suspended solids (TSS), organics (expressed by chemical oxygen demand, COD), and bisphenol A (BPA) via microfiltration (MF, pore size 0.45 µm) and ultrafiltration (UF, cutoff 150 kDa) in post-treatment of effluents from aerobic granular sludge reactors (GSBRs). The efficiency of removal of COD, BPA, and TSS in MF was similar to that in UF; however, it was achieved at a lower pressure, which reduces energy consumption during the filtration process. Despite the similar quality of the permeates in MF and UF, the permeate flux averaged almost 20% higher in UF than in MF. The rejection coefficients were 77-82% for COD and 48-100% for BPA. In both MF and UF, TSS were totally removed. In the integrated system of aerobic granular sludge reactor and membrane installation, total removal of COD was 92-95% and that of BPA was above 98%, independently of the membrane technique. The high efficiency of BPA removal in MF and UF, despite pore sizes in the MF and UF membranes larger than the BPA molecules, suggests that some part of the BPA was first bound by particulate organic matter in the biologically treated wastewater before this sorbed form was removed by the membranes. Furthermore, the high removal of COD and BPA, even in MF, was attributed to adsorption on the membranes, in addition to sieve retention.
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BACKGROUND: Lyme disease is on the rise in Canada. It is a notifiable disease, and when infection is disseminated, serological testing provides supplemental evidence to confirm a case. OBJECTIVE: To describe the current diagnostic tests for Lyme disease, review the recommended approach to laboratory testing for Lyme disease and identify future research priorities for Lyme disease laboratory diagnostics in Canada. METHODS: A review of the literature was carried out. We then summarized parameters to consider before Lyme disease testing is conducted, described the current best practice to use a two-tiered diagnostic algorithm for the laboratory confirmation of disseminated Lyme disease, and analyzed the advantages and disadvantages of the supplemental tests for Lyme disease. RESULTS: Diagnostic testing is indicated in people who have symptoms of disseminated disease and a history of exposure to vector ticks. To maximize sensitivity and specificity, a two-tiered serological approach is recommended, consisting of an enzyme immunoassay (EIA) screening test followed by confirmation with Western blot (WB) testing. A number of other diagnostic tests are available; however, these are largely for research purposes. CONCLUSION: Two-tiered serology is currently the best approach available to assist doctors when they are making a diagnosis of disseminated Lyme disease. The Public Health Agency of Canada (the Agency) will seek to improve on this approach through standardization of the Lyme disease diagnostics used across laboratories in Canada, evaluation of test performance characteristics of current and new diagnostic platforms and development of a process to secure robust serum panels to assist in the development and evaluation of new diagnostic tests for Lyme disease.
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This study investigated the effectiveness of denitrification under aerobic conditions depending on nitrogen forms in synthetic wastewater (ammonium, or ammonium and nitrite). Activated sludge was cultivated in a sequencing batch reactor with municipal wastewater enriched by acetate. Poly-beta-hydroxybutyrate (PHB) was accumulated in activated sludge to 0.35 g PHB g(-1) VSS. Activated sludge, cultivated in such conditions, was used in further experimental series. The duration of each series was 24 h. Two types of synthetic wastewater, with acetate as the carbon source, were used in this study. One type of wastewater contained only ammonium; the second one was enriched also by nitrite. The amount of nitrogen reduced by the microorganisms in the activated sludge was 22.5 mg N(red) l(-1) when ammonium was the only nitrogen source in wastewater, and a 3-fold increase was observed in the presence of two nitrogen sources: ammonium and nitrite. Simultaneous consumption of organic substances in wastewater (external source of electron donors) and intracellularly stored poly-beta-hydroxybutyrate in activated sludge (endogenous carbon source) was revealed. COD consumption to reduce 1 mg N-oxides, in series with wastewater containing ammonium, was 8.4 mg COD. However, in series using wastewater with ammonium and nitrite, a 3-fold decrease in COD/N(red) ratio was observed.
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Reactores Biológicos , Carbono/metabolismo , Hidroxibutiratos/metabolismo , Óxidos de Nitrógeno/química , Nitrógeno/metabolismo , Oxígeno/química , Poliésteres/metabolismo , Aerobiosis , Oxidación-Reducción , Aguas del Alcantarillado/químicaRESUMEN
The study aimed at identifying heterozygotic phenylketonuria gene carriers with phenylalanine tolerance test performed in Lublin region. Serum phenylalanine concentration has been assayed during fasting and 1 and 2 hours following oral phenylalanine load in the dose of 0.1 g per 1 kg body weight. The study involved 203 individuals of the general population and 29 heterozygotes with phenylketonuria gene. Blood serum phenylalanine was assayed with Guthrie' technique. Statistical analysis has shown that hyperphenylalaninemia is relatively frequent in fasting individuals of the general population (59.1%). The same was demonstrated in 5 heterozygotes. Phenylalanine tolerance test did not allow to identify heterozygotic carries of phenylketonuria gene in the general population though fasting and after phenylalanine load increased blood serum levels of this amino acid are a criterium of hyperphenylalaninemia in the group of tested individuals (29%).