Effect of the design of a tangential vortex generator on the characteristics of the involuted flow and carrying capacity of a spillway

Conclusions An involuting device in the form of a tangential vortex flow generator is the basic element of a vortex spillway, which defines the carrying capacity, the degree of flooding of the shaft, and the current regime of the involuted flow in the diversion tunnel of the spillway. The procedure employed for hydraulic calculation of vortex spillways with the vortex flow generators under consideration makes it possible to determine rather completely all basic characteristics of the involuted flow and on this basis, assume a serviceable design for the spillway on the whole. It is obvious that the problem concerning the influence exerted by aeration in shaft spillways on the characteristics of the involuted flow (kinematic, hydrodynamic) and the hydraulic losses of the elements of the spillway will be the subject of future research. Moreover, there are no data sufficient for predicting the development of cavitation in vortex generators with different geometric parameters. At the same time, experimental cavitation-erosion investigations for conditions encountered at the Rogun vortex spillway, which were performed at the MGUP, indicated that the cavitation flare, which is disturbed from the edge of the vortex generator, is steadily closed within the flow and does not present a risk from the standpoint of cavitation erosion. Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 2, pp. 24–27, February, 1999.     

Correlated ultrastructural and biochemical studies on the mechanisms of secretion of catecholamines

The frequency of dark-cored vesicles is compared with the content in catecholamines in the adrenal medulla and carotid body of normal and reserpine-treated cats. Reserpine produces important diminution in the content of catecholamines but the frequency of the dark-cored vesicles does not parallel this descent. In the carotid body there is no relation between the content in catecholamines and the number of granules. The diameter of the dark cores does not change with the number of secretion vesicles present in normal or treated specimens. It is concluded that there is not partial discharge of the content of the vesicles. An all-or-nothing mechanism of discharge of exocytotic type is proposed.     

The prognostic value of the tumour markers CA 195 and CEA in patients with adenocarcinoma of the pancreas

The serum levels of CA 195 were determined in 52 patients with histologically proven pancreatic carcinoma and compared with carcino-embryonic antigen (CEA), serum bilirubin and albumin. CA 195 levels were raised above the upper limit of 20 U/ml in 42 cases, giving a sensitivity of 80% for the detection of pancreatic carcinoma, whereas CEA was raised in only 55%. The levels of CA 195 and CEA were significantly higher in patients with metastatic disease, but potentially curable cases were not discriminated. Bilirubin and albumin levels were not significantly related to either the presence of metastases or the levels of the tumour markers. At the time of initial presentation, levels of both tumour markers correlated with the eventual duration of survival, but bilirubin and albumin did not. Significant increases in CEA and CA 195 were found in sequential blood samples, as the disease progressed. Neither CA 195 nor CEA was of sufficient sensitivity to be of value for screening, but both give an indication of the presence of metastases and of the subsequent duration of survival. CA 195 appeared to be more sensitive and might help to assess progress of the disease.     

Innate resistance to infection by intracellular bacterial pathogens differs in mice selected for maximal or minimal acute inflammatory response

PURPOSE: The mechanisms that underlie the clinical efficacy of melanoma vaccines are not well understood. We hypothesized that the type and strength of the immune response generated by CancerVax (John Wayne Cancer Institute, Santa Monica, CA), a polyvalent melanoma cell vaccine (PMCV), might be correlated with its effect on overall survival (OS). PATIENTS AND METHODS: Seventy-seven patients began PMCV therapy after complete surgical resection of distant metastatic melanoma. During the first two treatments, PMCV was administered with bacille Calmette-Guerin (BCG). Blood was drawn at 0, 2, 4, 8, and 12 weeks to measure serum titers of immunoglobulin G (IgG) and IgM antibodies against a tumor-associated 90-kd glycoprotein antigen (TA90) expressed on most melanoma cells, including those of PMCV. Cellular immune response to PMCV was assessed by delayed-type hypersensitivity (DTH). General immune competence was assessed by skin tests to purified protein derivative (PPD), mumps, and candida. RESULTS: Median follow-up time was 31.5 months. Within the first 12 weeks of PMCV immunotherapy, there was a significant increase in the anti-TA90 IgM (P=.0001) and IgG titers (P=.0001), and in the DTH response to PMCV (P=.0001). Univariate analysis showed that high anti-TA90 IgM titer and strong PMCV-DTH were associated with improved survival (P=.051 and .0173, respectively), whereas elevated anti-TA90 IgG was correlated with decreased survival (P=.0119). Multivariate analysis considering clinical variables and PMCV immune responses identified anti-TA90 IgM, anti-TA90 IgG, and PMCV-DTH as significant independent variables influencing survival following PMCV immunotherapy (P=.0342, .0105, and .0082, respectively). These responses to PMCV were not correlated with immune responses to BCG and therefore were not a manifestation of general immune competence for responses to unrelated antigens. The median survival time and 5-year survival rate were more than 76 months and 75%, respectively, if both anti-TA90 IgM and PMCV-DTH responses were strong (> or = 800 and > or = 7 mm, respectively; n=29); 32 months and 36%, respectively, if only one response was strong (n=35); and 19 months and 8%, respectively, if neither was strong (n=13) (P < .0001). CONCLUSION: PMCV induces both humoral and cell-mediated immune responses to melanoma-associated tumor antigens, the type and strength of which appear to be directly related to its therapeutic efficacy.     

Microbial communities of printing paper machines

The microbial content of printing paper machines, running at a temperature of 45-50 degrees C and at pH 4.5-5, was studied. Bacteria were prevalent colonizers of the machine wet end and the raw materials. A total of 390 strains of aerobic bacteria were isolated and 86% of these were identified to genus and species by biochemical, chemotaxonomic and phylogenetic methods. The most common bacteria found at the machine wet end were Bacillus coagulans and other Bacillus species, Burkholderia cepacia, Ralstonia pickettii, and in pink slimes, accumulating in the wire area and press section, species of Deinococcus, aureobacterium and Brevibacterium. Paper-making chemicals also contained species of Aureobacterium, B. cereus, B. licheniformis, B. sphaericus, Bordetella, Hydrogenophaga, Klebsiella pneumoniae, Pantoea agglomerans, Pseudomonas stutzeri, Staphylococcus and sometimes other enteric bacteria, but these did not colonize the process water. Yeasts and moulds were not present in significant numbers. A total of 131 strains were tested for their potential to degrade paper-making raw materials; 91 strains were found to have degradative activity, mainly species of Burkholderia and Ralstonia, Sphingomonas and Bacillus, and enterobacteria produced enzymes which degraded paper-making chemicals. Stainless steel adhering strains occurred in slimes and wire water and were identified as Burkholderia cepacia, B. coagulans and Deinococcus geothermalis. Coloured slimes were formed on the machine by species of Deinococcus, Acinetobacter and Methylobacterium (pink), Aureobacterium, Pantoea and Ralstonia (yellowish) and Microbulbifer-related strains (brown). The impact of the strains and species found in the printing paper machine community on the technical quality of paper, machine operation, and as a potential biohazard (Hazard Group 2 bacteria), is discussed.