Study of the sludge reduction in an oxic-settling-anaerobic activated sludge process based on UNITANK

An oxic-settling-anaerobic process (OSA) can effectively reduce sludge production, but most of the research studies on the OSA process have been either under laboratory test conditions or based on synthetic wastewater, which cannot fully reflect the performance and sludge reduction efficiency in existing OSA process. Thus, aiming at examining the sludge reduction efficiency and the stability of the OSA process, UNITANK and UNITANK-OSA processes were performed in a 120 m(3)/d pilot-scale system using actual sewage. The results indicate that UNITANK-OSA achieved a 48% reduction of the sludge compared to the reduction due to UNITANK, not considering the accumulation of the effluent-suspended solids. The effluent quality was not found to change significantly, except that the total phosphorus concentration increased slightly. The extracellular polymeric substances metal floc theory may, to some extent, explain this reduction in this study. The OSA process could be used to reform the classic wastewater treatment process to get lower sludge mass.

[Molecular tagging and mapping of QTLs for super quality fiber properties in upland cotton]

A G. anomalum introgression line, 7235, characterized as super quality fiber properties, was used to identify molecular markers linked to fiber property QTLs. By use of (7235 x TM-1)F2 in Nanjing and College Station, USA, and (7235 x TM-1)F3 in Nanjing and Hainan. Bulked segregation analysis was employed to produce 3 pairs of mixed DNA pools for fiber strength, micronaire and fiber length according to individual value of (7235 x TM-1)F2 and F2:3. A total of 221 pairs of SSR primers, 1,840 arbitrary 10-mer oligonucleotide primers and 77 ISSR primers were used to screen polymorphism between two parents, and 3 pairs of bulked DNA pools. Fifteen markers amplified by thirteen primers were identified to be linked with fiber quality QTLs through DNA polymorphism surveying between the parents, and then paired bulked DNAs, and screening the individual plant of (7235 x TM1)F2. Linkage test indicated 15 markers could be mapped to three linkage groups. In the first linkage group, eight markers (two SSR and six RAPD markers) associated with fiber strength were tightly linked with 2.2 cM interval genetic distance on average, and located on chromosome 10 in cotton. Two major QTLs for fiber quality characters were identified. One for fiber strength could explain 35% of the phenotypic variation in F2, and 53.8% in F2:3 at Hainan, which has the greatest single QTL effect of fiber strength and could be identified in all four environments, and tightly linked to 6 RAPD markers and 2 SSR markers with genetic distance no more than 16 cM in chromosome 10, in which FSRl933 is the nearest with the distance no more than 0.6 cM. One QTL linked to FMR1(603) for Micronaire could explain 7.8% of the phenotypic variation in F2, and 25.4% in F2:3 at Hainan, and expressed in all four environments. One QTL linked to FLR1(1550) for fiber length could explain 9.5% of the phenotypic variation in F2:3 at Hainan, very little in other environments. So they can be used in marker-assisted selection in increasing fiber quality of commercial cultivars.

[Investigation of different dosages of inserted Bt genes and their insect-resistance in transgenic Bt cotton]

The plants with various dosages of inserted Bt genes were developed by intercrossing among transgenic Bt lines in which Bt genes were inserted in different chromosomes, and commercial non-transgenic Bt varieties. Laboratory bioassay of insect-resistance and Bt toxin protein assays with ELISA were used to detect efficacy to bollworm in different cotton growing stages. As transgenic Bt insect-resistant cotton, temporal difference of resistance existed in plants converging on different dosages of inserted Bt genes, i.e., there was a declining level of efficacy with plant age as the mortality (%) of Helicoverpa and Bt toxin protein expressional level decreased gradually, when analyzed with leaves from the main stem. Our research also revealed that the insect-resistance of converging 4 Bt genes plants was decreased due to homozygous suppression.

[A report of 29 cases of silicosis complicated with mediastinal emphysema]

The experience to treat SCME in the past twenty-three years was reported. The method of upper mediastinotomy for saving the patients was introduced. The authors suggested control of the pulmonary infection and appropriate treatment of pneumothorax are important in preventing the occurrence of mediastinal emphysema.

Comparison of an enzyme-linked immunosorbent assay and a complement-fixation test for the detection of IgG to bovine herpesvirus type 4 (bovine cytomegalovirus)

An indirect ELISA for the detection of bovine immunoglobulin to bovine herpesvirus type 4 (BHV-4) was developed. Three methods of antigen preparation were compared. They included (1) BHV-4-infected Madin Darby bovine kidney (MDBK) cells treated with glycine and then frozen and thawed, (2) BHV-4-infected MDBK cells treated with glycine and then sonicated, and (3) BHV-4-infected MDBK cells treated with a detergent. The antigen preparation that gave the highest reactivity was the first method. We obtained serum samples from 178 cattle in the field and assayed the serum by ELISA and the complement-fixation (CF) test. Eighty-six percent (153) of the serum samples were positive by ELISA, and 70% (124) were positive by the CF test. The ELISA had a higher degree of sensitivity than did the CF test. Also, the ELISA was specific, and the prevalence of BHV-4-infection was more common in beef and dairy herds than previously recognized.