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1.
While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy.  相似文献   
2.
Tourism accounts for 9% of global GDP and comprises 1.1 billion tourist arrivals per annum. Visits to wildlife tourist attractions (WTAs) may account for 20–40% of global tourism, but no studies have audited the diversity of WTAs and their impacts on the conservation status and welfare of subject animals. We scored these impacts for 24 types of WTA, visited by 3.6–6 million tourists per year, and compared our scores to tourists’ feedback on TripAdvisor. Six WTA types (impacting 1,500–13,000 individual animals) had net positive conservation/welfare impacts, but 14 (120,000–340,000 individuals) had negative conservation impacts and 18 (230,000–550,000 individuals) had negative welfare impacts. Despite these figures only 7.8% of all tourist feedback on these WTAs was negative due to conservation/welfare concerns. We demonstrate that WTAs have substantial negative effects that are unrecognised by the majority of tourists, suggesting an urgent need for tourist education and regulation of WTAs worldwide.  相似文献   
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Characterization of host-pathogen interactions is a fundamental approach in microbiological and immunological oriented disciplines. It is commonly accepted that host cells start to change their phenotype after engulfing pathogens. Techniques such as real time PCR or ELISA were used to characterize the genes encoding proteins that are associated either with pathogen elimination or immune escape mechanisms. Most of such studies were performed in vitro using primary host cells or cell lines. Consequently, the data generated with such approaches reflect the global RNA expression or protein amount recovered from all cells in culture. This is justified when all host cells harbor an equal amount of pathogens under experimental conditions. However, the uptake of pathogens by phagocytic cells is not synchronized. Consequently, there are host cells incorporating different amounts of pathogens that might result in distinct pathogen-induced protein biosynthesis. Therefore, we established a technique able to detect and quantify the number of pathogens in the corresponding host cells using immunofluorescence-based high throughput analysis. Paired with multicolor staining of molecules of interest it is now possible to analyze the infection profile of host cell populations and the corresponding phenotype of the host cells as a result of parasite load.  相似文献   
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Abstract: The glial fibrillary acidic protein (GFAP) content was investigated using immunoblotting techniques in the septum and hippocampus of the rat after bilateral lateral fimbria transection. Seven days after surgery GFAP content increased significantly both in the septum (140% of control) and hippocampus (120% in dorsal, the less denervated, and 145% in the most denervated ventral part), indicating the occurrence of reactive gliosis. The GM1 treatment caused statistically significant attenuation of GFAP increment in all hippocampal parts. In contrast, GM1 treatment has no influence on the increase of GFAP content in the septum. Results suggest a differential effect of GM1 on the two gliotic reactions formed as a consequence of the lesion at the level of the source of innervation (septum) and the target (hippocampus).  相似文献   
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Abstract. The in vitro proliferation [uptake of 5-bromo-2'-deoxyuridine (BrdU)] and the degree of differentiation (presence of desmin) of myosatellite cells isolated from white axial muscle of carp between 3 cm and 27 cm standard length (SL) were examined 17 h after isolation. The fraction of the myosatellite cells that were both desmin positive and BrdU positive never exceeded 2% of the total number of isolated myosatellite cells, irrespective of the standard length of the donor(s). This indicates that, for carp, the temporal relationship between replication and desmin expression of myosatellite cells is different from that described for myogenic cells of mammals and birds. The percentage of BrdU positive myosatellite cells was significantly correlated with standard length: it increased from 10% for carp of about 5 cm SL to 40–50% for carp between 20 cm and 27 cm SL. The percentage of desmin positive myosatellite cells was about 50–60%; it was not significantly correlated with standard length. The percentage of myosatellite cells that were both BrdU negative and desmin negative showed a stepwise difference in this percentage with increasing length. Fish smaller than 10 cm SL, had more of these cells (10–40%), than larger fish (which had 0–12%). So, apparently the composition of the myosatellite cell population changes during growth. The low percentage of proliferating cells, and the relatively high percentage of differentiated (desmin positive) myosatellite cells obtained from 3–6 cm large carp, suggests that, in these small fish, muscle growth strongly depends on the use of a pool of myogenic cells that has been formed at an earlier stage of their development.  相似文献   
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Sink strength: Learning to measure, measuring to learn   总被引:1,自引:0,他引:1  
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