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Poaching and habitat destruction in the Congo Basin threaten African great apes including the bonobo (Pan paniscus), chimpanzees (Pan troglodytes), and gorillas (Gorilla spp.) with extinction. One way to combat extinction is to reintroduce rescued and rehabilitated apes and repopulate native habitats. Reintroduction programs are only successful if they are supported by local populations. Ekolo ya Bonobo, located in Equateur province of the Democratic Republic of Congo (DRC), is the world's only reintroduction site for rehabilitated bonobos. Here we assess whether children, of the Ilonga‐Pôo, living adjacent to Ekolo ya Bonobo demonstrate more pro‐ape conservation attitudes than children living in, Kinshasa, the capital city. We examined children's attitudes toward great apes because children are typically the focus of conservation education programs. We used the Great Ape Attitude Questionnaire to test the Contact Hypothesis, which posits that proximity to great ape habitat influences pro‐conservation attitudes toward great apes. Ilonga‐Pôo children who live in closer contact with wild bonobos felt greater responsibility to protect great apes compared to those in Kinshasa who live outside the natural habitat of great apes. These results suggest that among participants in the DRC, spatial proximity to a species fosters a greater sense of responsibility to protect and conserve. These results have implications for the successful implementation of great ape reintroduction programs in the Congo Basin. The data analyzed in this study were collected in 2010 and therefore provide a baseline for longitudinal study of this reintroduction site.  相似文献   
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Exposure of pronghorns (Antilocapra americana) in western Nebraska in 1983 to selected livestock pathogens was examined by serology and attempted virus isolation. Antibodies were present to the agents of bluetongue, epizootic hemorrhagic disease, and bovine respiratory syncytial virus. There were no serologic reactors to Brucella, and attempts to isolate the viruses of bluetongue and epizootic hemorrhagic disease were negative.  相似文献   
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Growth curves of the 5 commonly used Ames Salmonella tester strains have been measured turbidimetrically in semi-solid agar. Lag times, doubling times and maximum cell densities have been calculated for each of the 5 strains. The time dependence of reversion has been studied in the standard plate incorporation assay using 1-h pulsed doses of (a) bromoethane, a volatile chemical mutagen, and (b) 1-h exposures to visible light. Essentially no reversion takes place during the first 4 h after plating. Reversion is detectable between hours 4 and 16. The cumulative or integrated revertants versus time curve has the characteristics of a growth curve. Conversely the derivatives of the growth curves resemble the curves obtained in the pulsed mutagenicity studies. Thus, the reversion rate in any given 1 h interval is proportional to the growth rate during that same interval. These results suggest that mutagenic chemicals must be present during the bacterial growth cycle (about 4-16 h after plating) in order to revert the tester strains. Short-lived chemical mutagens, then, should produce enhanced results if plated 6-8 h after the bacteria. We have confirmed this for N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), 9-aminoacridine and 2-aminoanthracene (with S9).  相似文献   
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The net entry of galactose into the tissue of snail everted intestinal rings with 2 or 15 minute long incubation periods has been measured. With 10(-4) M phlorizin, the mediated transport is completely blocked while only the passive entry of sugar is produced. Lower concentrations of the glycoside partially inhibit transport according to competitive inhibition kinetics (K1 = 10(-7) M). The transport of galactose is Na+ dependent. In the absence of Na+, transport ceases and the sugar entry can be explained through simple diffusion. With 15 mM Na+ (control 71,4 mM) transport diminishes and a marked increase in the apparent Km with no changes in the Vmax is observed. One mM harmaline completely blocks galactose (0.5 mM) transport. One mM ouabain also makes transport null, but only after tissue preincubation with the inhibitor on the serosal side.  相似文献   
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