Comparing cost and process performance of activated sludge (AS) and biological aerated filters (BAF) over ten years of full sale operation.

In the early 1990s, the Wastewater Treatment Plant (WWTP) of Frederikshavn, Denmark, was extended to meet new requirements for nutrient removal (8 mg/L TN, 1.5 mg TP/L) as well as to increase its average daily flow to 16,500 m(3)/d (4.5 MGD). As the most economical upgrade of the existing activated sludge (AS) plant, a parallel biological aerated filter (BAF) was selected, and started up in 1995. Running two full scale processes in parallel for over ten years on the same wastewater and treatment objectives enabled a direct comparison in relation to operating performance, costs and experience. Common pretreatment consists of screening, an aerated grit and grease removal and three primary settlers with chemical addition. The effluent is then pumped to the two parallel biological treatment stages, AS with recirculation and an upflow BAF with floating media. The wastewater is a mixture of industrial and domestic wastewater, with a dominant discharge of fish processing effluent which can amount to 50% of the flow. The maximum hydraulic load on the pretreatment section as a whole is 1,530 m(3)/h. Approximately 60% of the sewer system is combined with a total of 32 overflow structures. To avoid the direct discharge of combined sewer overflows into the receiving waters, the total hydraulic wet weather capacity of the plant is increased to 4,330 m(3)/h, or 6 times average flow. During rain, some of the raw sewage can be directed through a stormwater bypass to the BAF, which can be modified in its operation to accommodate various treatment needs: either using simultaneous nitrification/denitrification in all filters with recirculation introducing bottom aeration with full nitrification in some filters for storm treatment and/or post-denitrification in one filter. After treatment, the wastewater is discharged to the Baltic Sea through a 500 m outfall. The BAF backwash sludge, approximately 1,900 m(3) per 24 h in dry weather, is redirected to the AS plant. Primary settler sludge and the combined biosolids from the AS plant are anaerobically digested, with methane gas being used for generation of heat and power. On-line measurements for the parameters NO3, NO2, NH4, temperature as well as dissolved oxygen (DO) are used for control of aeration and external carbon source (methanol). Dosing of flocculants for P-removal is carried out based on laboratory analysis and jar tests. This paper discusses the experience gained from the plant operation during the last ten years, compiling comparative performance and cost data of the two processes, as well as their optimisation.

Low free and total insulinlike growth factor I (IGF-I) and IGF binding protein-3 levels in chronic inflammatory bowel disease: partial normalization during prednisolone treatment.

OBJECTIVES: Catabolism and growth impairment are well known complications of chronic inflammatory bowel disease (CIBD). This may be caused by disease activity itself and/or the medical treatment, which may lead to changes in the growth hormone and insulinlike growth factor I (IGF-I) axis. Interest has focused on corticosteroids, as they are known to influence the growth hormone/IGF-I axis. METHODS: The aim of the present study was to examine changes in total and free IGF-I, IGF binding proteins (IGFBPs), and IGFBP-3 protease activity in 10 patients with severe acute activity in colon CIBD before and during high dose prednisolone treatment (1 wk) and 3 months tapering. Eight healthy subjects served as controls. RESULTS: Total and free IGF-I were significantly reduced by 35% and 53%, respectively, before prednisolone treatment (p < 0.05), and free IGF-I remained reduced even by the end of the study period relative to controls (p < 0.05). IGFBP-3 was reduced by 16% before (p < 0.05), with normalization during prednisolone treatment and tapering relative to controls. There was no evidence of increase in IGFBP-3 protease activity. IGFBP-1 was increased before and tended also to be increased during prednisolone treatment and tapering. CONCLUSIONS: Marked changes in serum total and free IGF-I and IGFBPs were demonstrated in patients with severe exacerbation of CIBD without complete normalization during high dose prednisolone treatment and tapering. These changes may partly be involved in the catabolism of active CIBD patients.

The effect of cisapride in maintaining symptomatic remission in patients with gastro-oesophageal reflux disease.

BACKGROUND: Successful treatment of gastro-oesophageal reflux disease (GORD) has traditionally been assessed as healing of reflux oesophagitis, which may not be relevant in patients with moderate disease. In these patients symptom relief and patient satisfaction with therapy are of fundamental importance. Cisapride has well-documented prokinetic effects and may be well suited for long-term therapy of GORD, but its effectiveness in purely symptomatic treatment is unknown. We therefore compared two dosage regimens of cisapride with placebo over a period of 6 months in patients with evidence of gastrooesophageal reflux, initially treated with antisecretory medication, with regard to maintaining symptom relief and satisfaction with treatment. METHODS: Five hundred and thirty-five patients with reflux oesophagitis grade 1 (n = 293) or 2 (n = 124) or with no reflux oesophagitis but pathologic 24-h pH-metry (n = 118) achieved satisfactory symptom relief with an H2-receptor antagonist or proton pump inhibitor within 4-8 weeks. In a double-blind randomized, parallel-group study, they were then treated with cisapride, 20 mg at night or 20 mg twice daily, or placebo and followed up for a maximum period of 6 months. Relapse was defined as dissatisfaction with therapy or an average consumption of more than two antacid tablets a day. RESULTS: Median time to relapse was 63 days for cisapride, 20 mg twice daily; 59 days for cisapride, 20 mg at night; and 49 days for placebo. Time to relapse was not significantly different (P = 0.09). Presence and grade of oesophagitis at base line, type of therapy before randomization, and pattern of non-reflux symptoms at base line did not influence these findings significantly. CONCLUSION: The study indicates that cisapride is of limited value in maintenance therapy of GORD in patients in whom symptom relief has been accomplished with potent antisecretory medication. This 'step-down' approach to therapy seems disadvantageous in the long-term therapy of GORD.

Unbalanced translocation between chromosomes 2 and 7 with de novo deletion of band 35 on the long arm of chromosome 2.

Clinical and cytogenetical findings are described in an infant with a de novo deletion of the long arm of chromosome 2. The boy's karyotype is 46,XY, rec(2)delq,t(2;7) (2pter----2q34::7p21----7pter) (7qter----7p21::2q36----2qter). He showed developmental retardation, low-set ears, micrognathia, short, neck, abundant skin of the neck, tetralogy of Fallot, bipartite labialike scrotum, clitorislike penis, cryptorchism, and deformities of the hands and feet.