The inhibition effects of total ammonia nitrogen (TAN) on aceticlastic methanogenic activity using biomass from thermophilic anaerobic reactors were investigated in this study. Anaerobic Toxicity Assays (ATA) were conducted after the biomass was acclimated to different levels of TAN. The TAN background concentrations in the reactors were 400, 1,200, and 3,050 mg/L. The results from ATA showed: 1) high TAN concentrations could cause inhibition of aceticlastic methanogens; 2) biomass acclimated to higher TAN concentrations could alleviate the inhibition effect due to the increase of TAN concentration; 3) the lethal TAN concentration for methanogens was approximately 10,000 mg/L regardless of the background TAN concentration; 4) ATA results also revealed the role played by pH. At a given TAN concentration, methanogenic activity varied with the pH values. The highest methanogenic activity was always observed at a pH of 7.0-7.5. 5) It was also observed that acclimation could increase the pH tolerance range, which made methanogens less sensitive to pH changes.

Sulfate-reducing bacteria (SRB) have been identified as the main corrosive microorganisms causing unpredictable failure of materials. In this present work, a strain of thermophile SRB isolated from Bohai oilfield of China has been characterized and preliminarily identified. Furthermore, its effects on carbon steel at 60 8C in SRB culture media were studied by electrochemical methods such as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), and weight loss measurements. The results show that the bacteria belong to Desulfotomaculum. The optimum growth temperature and pH of the bacteria were 60 8C and 7.0, respectively. Weight loss measurements suggested that the corrosion rate of carbon steel in the culture media inoculated with thermophile SRB at 60 8C was 2.2 times less than that at 37 8C. At 60 8C, SRB shifted the freely corroding potential of carbon steel toward a more positive value in the first 10 days, which later change to a negative value. Results obtained from potentiodynamic polarization and EIS were in good agreement. The changes in biofilm structure with increase in bacteria supply offers some kind of protection to the base material in the early culture days at 60 8C. Subsequently, it accelerated corrosion. Energy dispersive spectrometry (EDS) and X-ray diffraction (XRD) methods indicate that corrosion products such as iron sulfides (FeS x ) in biofilm play an important role in the biocorrosion process.

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done in 5/40 patients on diagnosis. Bone marrow infiltration was detected by PET/CT in 7/35 (20%) and by BMB in 5/35 (14%) cases.There was concordance between PET/CT and BMB in 27 patients (77%), 25 with negative PET/CT and BMB results and 2 with positive PET/CT and BMB results. Discordant results were observed in 8 patients. The sensitivity, specificity, positive predictive value and negative predictive value (NPV) of PET/CT for bone marrow involvement were 40%, 83%, 28.5% and 89%, respectively.Conclusions: Our study shows that 90% of PTCL are FDG avid at baseline, as one would expect with aggressive lymphoma. As the NPV of PET/CT for BM involvement is high, a negative PET/CT rules out bone marrow involvement.