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Landscape-scale approaches to conservation stem largely from the classic ideas of reserve design: encouraging bigger and more sites, enhancing connectivity among sites, and improving habitat quality. Trade-offs are imposed between these four strategies by the limited resources and opportunities available for conservation programmes, including the establishment and management of protected areas, and wildlife-friendly farming and forestry. Although debate regarding trade-offs between the size, number, connectivity and quality of protected areas was prevalent in the 1970–1990s, the implications of the same trade-offs for ongoing conservation responses to threats from accelerating environmental change have rarely been addressed. Here, we reassess the implications of reserve design theory for landscape-scale conservation, and present a blueprint to help practitioners to prioritise among the four strategies. We consider the new perspectives placed on landscape-scale conservation programmes by twenty-first century pressures including climate change, invasive species and the need to marry food security with biodiversity conservation. A framework of the situations under which available theory and evidence recommend that each of the four strategies be prioritized is provided, seeking to increase the clarity required for urgent conservation decision-making.  相似文献   
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Prey species must adapt their behavior to avoid predation. Asa key prey item for lions (Panthera leo), plains zebras (Equusburchelli) were expected to respond to immediate threats posedby lions in their area. In addition, zebras were predicted toexhibit behavior tuned to reduce the potential for encounterswith lions, by modifying their movement patterns in the timesof day and habitats of greatest lion danger. We studied a populationof approximately 600 plains zebra living in Ol Pejeta Conservancy,Kenya. We found that zebra abundance on or near a grasslandpatch was lower if lions had also been observed on that patchduring the same day. Predation danger was highest in grasslandhabitat during the night, when lions were more active. Zebrasightings and global positioning system radio collar data indicatedthat zebras also reduced their use of grassland at night, insteadusing more woodland habitat. Zebras moved faster and took sharperturns in grassland at night. It is hypothesized that these moreerratic movements assist zebras in avoiding detection or captureby lions.  相似文献   
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Radiation and Environmental Biophysics - Dose- and dose rate-dependent increase in the number of СD3+СD16+CD56+-lymphocytes and lysosomal activity of neutrophils was noted in peripheral...  相似文献   
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Microtubule (MT) protein preparations often contain components of the translation machinery, including ribosome proteins. To understand the biological meaning of it we studied the interaction of ribosomal protein RPL22e with the MT. We found that bacteria expressed purified RPL22e‐GFP‐6His did co‐sediment with brain tubulin MTs with 1.3 µM dissociation coefficient. Such a KD is comparable to some specific MT‐associated proteins. Distinct in vitro interaction of RPL22e‐GFP with MTs was also observed by TIRF microscopy. In real‐time assay, RPL22e‐GFP molecules stayed bound to MTs for several seconds, and 15% of them demonstrated random‐walk along MTs with diffusion coefficient 0.03 µ2/s. Deletion of basic areas of RPL22e did not have an impact on KD, and deletion of acidic tail slightly increased association with MTs. Interestingly, the deletion of acidic tail increased diffusion coefficient as well. The interaction of RPL22e with MTs is hardly noticeable in vivo in cultured cells, probably since a significant part of the protein is incorporated into the ribosomes. The mobility of ribosomal protein on the MTs probably prevents its interfering with MT‐dependent transport and could ameliorate its transport to the nucleus.  相似文献   
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This study compares temporal patterns of intraspecific agonistic interactions in two gerbil species in order to indicate interspecific differences in levels of social resistance. Both cross-sex and same-sex pairs of great gerbils (Rhombomys opimus Licht., 1823), and only same-sex male pairs of pallid gerbils (Gerbillus perpallidus Setzer 1958) were observed during staged encounters on a neutral arena. Analysis of three latency measures—latency to first agonistic interaction; latency to overt aggression (attack and/or ‘arrested’ fight); and latency to establishment of a stable winner-loser asymmetry among opponents—revealed both similarities and differences among the species. Latencies to first agonistic interaction were similar (did not differ significantly) among species and sexes. However, great gerbil males showed significantly more long latencies to establishment of a stable asymmetry among opponents, than great gerbil females or pallid gerbil males. So, the periods of symmetrical struggle in agonistic conflict last longer in great gerbil males, than in great gerbil females or pallid gerbil males. These differences in temporal pattern of agonistic interaction may reflect sex and species differences in resistance to social stress.  相似文献   
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Biochemistry (Moscow) - Huntington’s disease (HD) is a neurodegenerative, dominantly inherited genetic disease caused by expansion of the polyglutamine tract in the huntingtin gene. At the...  相似文献   
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