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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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Membrane-associated GTPases in bacteria   总被引:9,自引:0,他引:9  
Members of the GTPase superfamily are extremely important in regulating membrane signalling pathways in all cells. This review focuses on membrane-associated GTPases that have been described in prokaryotes. In bacteria, LepA and NodQ are very similar to protein synthesis elongation factors but apparently have membrane-related functions. The amino acid sequences of FtsY and Ffh are clearly related to eukaryotic factors involved in protein secretion. Obg and Era are not closely related to any GTPase subgroup according to amino acid sequence comparisons, but they are essential for viability. In spite of similarities to well-studied eukaryotic proteins the signalling pathways of these cellular regulators, with the exception of NodQ, have not yet been elucidated.  相似文献   
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Carotid intima-media thickness (cIMT) is a surrogate marker of early atherosclerotic changes in children. cIMT-studies are hard to compare, due to variations in ultrasound protocols, especially regarding the common carotid artery (CCA) segment measured in relation to the bulb. This study’s purpose was therefore to compare two distinct CCA segments in children, to see if cIMT values differ substantially according to the site of measurement. cIMT was assessed after power calculation in 30 children (15 girls) aged 8–17, using B-Mode ultrasound (5–13 MHz) at two CCA locations. The first measurement was performed over a distance of 1 cm immediately after the bulb (A), the second 1cm proximal the bulb (B) over the same distance of 1cm length. Means of end-diastolic far wall cIMT were compared between measurement A and B. cIMT in 30 participants was 0.51±0.06 mm for measurement A and 0.51±0.05 mm for measurement B. Results did not differ significantly (p = .947) over a distance of 2 cm after the bulb. According to our results, studies measuring CCA IMT within the first 2 cm, either close to the bulb or further proximal, can be compared. This will improve interpretation of data and application of reference values.  相似文献   
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Era is a membrane-associated GTP-binding protein which is essential for cell growth in Escherichia coli. In order to examine the physiological role of Era, strains in which Era was expressed at 40 degrees C but completely repressed at 27 degrees C were constructed. The growth of these strains was inhibited at the nonpermissive temperature, and cells became elongated. Under such conditions, no constrictions or septum formation could be detected by phase-contrast microscopy, and DNA segregation was apparently normal as revealed by fluorescence staining. These data demonstrate that Era has an essential function in cell growth rate control in liquid media and that depletion of Era blocks cell division either directly or indirectly. Thus, the role of GTP-binding proteins as important regulators of cell growth and division may be ubiquitous in nature.  相似文献   
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