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Members of the family Vibrionaceae are generally found in marine and brackish environments, playing important roles in nutrient cycling. The Rumoiensis clade is an unconventional group in the genus Vibrio, currently comprising six species from different origins including two species isolated from non-marine environments. In this study, we performed comparative genome analysis of all six species in the clade using their complete genome sequences. We found that two non-marine species, Vibrio casei and Vibrio gangliei, lacked the genes responsible for algal polysaccharide degradation, while a number of glycoside hydrolase genes were enriched in these two species. Expansion of insertion sequences was observed in V. casei and Vibrio rumoiensis, which suggests ongoing genomic changes associated with niche adaptations. The genes responsible for the metabolism of glucosylglycerate, a compound known to play a role as compatible solutes under nitrogen limitation, were conserved across the clade. These characteristics, along with genes encoding species-specific functions, may reflect the habit expansion which has led to the current distribution of Rumoiensis clade species. Genome analysis of all species in a single clade give us valuable insights into the genomic background of the Rumoiensis clade species and emphasize the genomic diversity and versatility of Vibrionaceae.  相似文献   
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Evidence was obtained that Eastern lowland gorillas feed regularly on ants in the lowland forests of eastern Zaire. The six species of ants that may have been consumed by the gorillas were identified as Ponerinae, which possess a painful sting. Gorillas consumed the ants in both rainy and dry seasons, and fragments of ants were found in fecal samples from gorillas of all age-sex classes. Field signs indicated that the gorillas search intensively ants in primary and ancient secondary forests. Such searching may stimulate the gorillas to range through various types of vegetation and, thus, it may contribute to elongation of the distances that they travel daily.  相似文献   
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We produced 102 randomly amplified polymorphic DNA (RAPD) markersmapped on all 12 chromosomes of rice using DNAs of cultivarsNipponbare (japonica) and Kasalath (indica) and of F2 populationgenerated by a single cross of these parents. Sixty random primers10 nucleotides long were used both singly and in random pairsand about 1,400 primer-pairs were tested. Using both agarosegel and polyacrylamide gel electrophoresis enabled us to detectpolymorphisms appearing in the range from <100 bp to 2 kb.The loci of the RAPD markers were determined onto the frameworkof our RFLP linkage map and some of these markers were mappedto regions with few markers. Out of the 102 RAPD markers, 20STSs (sequence-tagged sites) and STS-specific primer pairs weredetermined by cloning, identifying and sequencing of the mappedpolymorphic fragments.  相似文献   
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Background  

The α-EEG anomaly during sleep, originally associated with chronic pain, is noted in several psychiatric and medical conditions and is also present in some normal subjects. The exact significance of the α-EEG anomaly is uncertain, but it has been suggested to be a nonspecific response to a variety of noxious stimuli. We propose that attachment insecurity, which is often associated with a state of hypervigilance during wakefulness, may be associated with the α-EEG anomaly during sleep.  相似文献   
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The early stages of colonization by Tetraponera (= Pachysima) aethiops (Pseudomyrmecinae) to its obligate host plant, Barteria fistulosa (Passifloraceae), was studied in Kahuzi-Biega National Park, Democratic Republic of Congo (formerly Zaire). In our observations, as many as 36 queens colonized a seedling, and all of the established colonies had just a single queen each. The ants depend totally on the products of scale insects which inhabit the domatia. The ants damage the terminal meristems of the branches where other incipient colonies may inhabit. This tip-biting behavior may deteriorate the nutritional condition of scale insects and suppress the growth of the competing colonies. Ants pruned the plants near the edge of the trunk of the host tree most intensively, even the foliage of the lowest branch in shade. This observation supports the hypothesis that the main driving force which leads to pruning behavior is intercolony competition rather than improving the light condition of the host tree.  相似文献   
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