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831.
Fish passage structures are built to restore the connectivity of rivers and allow the migration of aquatic fauna. In order
to assess the functioning of a pool-type fishway, it is necessary, inter alia, to possess detailed knowledge of its flow structure,
since observations of fishways, and in particular of the visible water surface, can only provide a rough idea of the actual
conditions inside the pools. Numerical simulation has been used for many years to support engineering sciences. Especially,
the modeling of flow processes in hydraulic machines can, on the one hand, help avoid major problems during the design stage
of fish passage structures and, on the other, improve the structure’s hydraulic performance. To this end, two diploma theses
within the framework of a research project of the local energy supplier Energie Baden-Württemberg AG (EnBW) employed modeling
tools for 3D flow simulation, primarily for pool-slot fishways (PSF), and for traditional vertical slot fishways (VSF).
Guest editors: R. L. Welcomme & G. Marmulla
Hydropower, Flood Control and Water Abstraction: Implications for Fish and Fisheries 相似文献
832.
Margit Koller Michael Kundi Hans-Gü nter Stidl Thomas Zidek Manfred Haider 《Chronobiology international》1993,10(2):143-155
Light exposure was measured in six day and six night watches (working 12-hour shifts five days in a row) during 48 h on work days and 48 h on days off using a photocell with a sensitivity corresponding to photopic vision. The photocell was mounted on a frame of spectacles, thus measuring in viewing direction. Light exposure was low both in night and day watches; however, in night watches exposures were significantly lower: On work days, night watches spent a mean of 13 min above 1,500 lx, day watches 52 min; on days off, night watches spent 3 min above 1,500 lx but day watches 89 min. Unexpectedly, night watches had no higher exposure during days off. We suspect that this is due to a light avoidance tendency in permanent night workers. High negative correlations between the acrophases of subjective state (e.g., alertness and mood) and light exposure in night watches indicate that bright light would probably increase desynchroniza-tion between subjective state, sleep, and activity. 相似文献
833.
Margit Zuber 《Molecular biology reports》1996,23(3-4):197-203
Analysis of reactivity to nuclear antigens in autoimmune sera revealed a serum that produced a previously undescribed cell cycle-dependent immunofluorescence staining pattern. By indirect immunofluorescence using HEp-2 cells as substrate, the serum generated a speckled and nucleolar pleomorphic staining pattern. This characteristic immunofluorescence pattern was detected in different cell lines from various species indicating that the antigen was highly conserved. This serum immunoprecipitated a 85 kDa protein using an extract from [35S]-labeled HeLa cells. Indirect immunofluorescence of proliferating mouse 3T3 cells displayed the characteristic pleomorphic staining which was not observed in serum-starved cells. Resting human and mouse peripheral blood lymphocytes were negative in immunofluorescence while mitogen-stimulated lymphocytes were positive. Germinal centers of mice two weeks after immunization with 2-phenyl-oxazolone showed speckled immunofluorescence staining in the dark zones whereas unimmunized mice were completely negative. Cell synchronization experiments showed a characteristic sequence of locations of the antigen during the cell cycle. In G1, cells were completely negative. In late G1, G1/S and S phase, speckles were visible. In early G2, speckles were visible, and later in G2, the nucleoli were positive. During mitosis chromosomes were stained. Further characterization of this antibody specificity and cloning of cDNA are in progress. 相似文献
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Brahma S. Sharma Louisa Balazs Ai Jin James Chyan-Ji Wang Weldon B. Jolley Roland K. Robins 《Cancer immunology, immunotherapy : CII》1991,33(2):109-114
Summary We have investigated the ability of a novel immunopotentiator, 7-thia-8-oxoguanosine (7T8OG) to increase the efficacy of a weakly immunogenic murine L1210 leukemia vaccine. The vaccine was prepared by irradiating L1210 leukemia cells in a cesium source with a total of 6000-R dose. DBA/2 mice were treated with 150 mg/kg 7T8OG and/or with vaccine consisting of 107 irradiated cells. In combination therapy, mice first received the vaccine and then were injected with 75 mg/kg 7T8OG 2 h and 4 h after vaccination. One week after the last treatment all mice were inoculated with 104 live leukemia cells intraperitoneally. Control, untreated mice (n = 66) injected with 104 live leukemia cells had a mean survival time ± standard error of 10.5±0.2 days. Treating mice (n = 66) with one, two or three doses of 7T8OG administered i.p. 1 week apart did not increase survival (mean survival time = 10.7 days). Mice immunized with one, two or three doses of vaccine had 14.5±1.1, 45.4±6.2 and 68.3±10.6 days mean survival, respectively. 7T8OG-stimulated vaccination increased the survival dramatically. The best survival was noted when the mice were treated with 2× (vaccine + 7T8OG). Immunization of mice (n = 30) with this treatment regimen increased the mean survival to 156±10.0 days. Over 90% of mice that were treated this way had a cumulative survival time greater than 160 days. In contrast, only 12% of the mice immunized twice with the leukemia vaccine alone survived over 160 days. These results suggest a rationale for the use of this immuno-potentiator with various vaccines for a more effective immunization. 相似文献
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