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941.
Streptobacillus moniliformis Levaditi et al. 1925 is the type and sole species of the genus Streptobacillus, and is of phylogenetic interest because of its isolated location in the sparsely populated and neither taxonomically nor genomically much accessed family 'Leptotrichiaceae' within the phylum Fusobacteria. The 'Leptotrichiaceae' have not been well characterized, genomically or taxonomically. S. moniliformis,is a Gram-negative, non-motile, pleomorphic bacterium and is the etiologic agent of rat bite fever and Haverhill fever. Strain 9901(T), the type strain of the species, was isolated from a patient with rat bite fever. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is only the second completed genome sequence of the order Fusobacteriales and no more than the third sequence from the phylum Fusobacteria. The 1,662,578 bp long chromosome and the 10,702 bp plasmid with a total of 1511 protein-coding and 55 RNA genes are part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
942.
Jonesia denitrificans (Prevot 1961) Rocourt et al. 1987 is the type species of the genus Jonesia, and is of phylogenetic interest because of its isolated location in the actinobacterial suborder Micrococcineae. J. denitrificans is characterized by a typical coryneform morphology and is able to form irregular nonsporulating rods showing branched and club-like forms. Coccoid cells occur in older cultures. J. denitrificans is classified as a pathogenic organism for animals (vertebrates). The type strain whose genome is described here was originally isolated from cooked ox blood. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is the first completed genome sequence of a member of the genus for which a complete genome sequence is described. The 2,749,646 bp long genome with its 2558 protein-coding and 71 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
943.
Thermanaerovibrio acidaminovorans (Guangsheng et al. 1997) Baena et al. 1999 is the type species of the genus Thermanaerovibrio and is of phylogenetic interest because of the very isolated location of the novel phylum Synergistetes. T. acidaminovorans Su883(T) is a Gram-negative, motile, non-spore-forming bacterium isolated from an anaerobic reactor of a sugar refinery in The Netherlands. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first completed genome sequence from a member of the phylum Synergistetes. The 1,848,474 bp long single replicon genome with its 1765 protein-coding and 60 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
944.
Halogeometricum borinquense Montalvo-Rodríguez et al. 1998 is the type species of the genus, and is of phylogenetic interest because of its distinct location between the halobacterial genera Haloquadratum and Halosarcina. H. borinquense requires extremely high salt (NaCl) concentrations for growth. It can not only grow aerobically but also anaerobically using nitrate as electron acceptor. The strain described in this report is a free-living, motile, pleomorphic, euryarchaeon, which was originally isolated from the solar salterns of Cabo Rojo, Puerto Rico. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the halobacterial genus Halogeometricum, and this 3,944,467 bp long six replicon genome with its 3937 protein-coding and 57 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.  相似文献   
945.
Arenaviruses are the causative pathogens of severe hemorrhagic fever and aseptic meningitis in humans, for which no licensed vaccines are currently available. Pathogen heterogeneity within the Arenaviridae family poses a significant challenge for vaccine development. The main hypothesis we tested in the present study was whether it is possible to design a universal vaccine strategy capable of inducing simultaneous HLA-restricted CD8+ T cell responses against 7 pathogenic arenaviruses (including the lymphocytic choriomeningitis, Lassa, Guanarito, Junin, Machupo, Sabia, and Whitewater Arroyo viruses), either through the identification of widely conserved epitopes, or by the identification of a collection of epitopes derived from multiple arenavirus species. By inoculating HLA transgenic mice with a panel of recombinant vaccinia viruses (rVACVs) expressing the different arenavirus proteins, we identified 10 HLA-A02 and 10 HLA-A03-restricted epitopes that are naturally processed in human antigen-presenting cells. For some of these epitopes we were able to demonstrate cross-reactive CD8+ T cell responses, further increasing the coverage afforded by the epitope set against each different arenavirus species. Importantly, we showed that immunization of HLA transgenic mice with an epitope cocktail generated simultaneous CD8+ T cell responses against all 7 arenaviruses, and protected mice against challenge with rVACVs expressing either Old or New World arenavirus glycoproteins. In conclusion, the set of identified epitopes allows broad, non-ethnically biased coverage of all 7 viral species targeted by our studies.  相似文献   
946.
Reports of rapid growth in nature-based tourism and recreation add significant weight to the economic case for biodiversity conservation but seem to contradict widely voiced concerns that people are becoming increasingly isolated from nature. This apparent paradox has been highlighted by a recent study showing that on a per capita basis, visits to natural areas in the United States and Japan have declined over the last two decades. These results have been cited as evidence of “a fundamental and pervasive shift away from nature-based recreation”—but how widespread is this phenomenon? We address this question by looking at temporal trends in visitor numbers at 280 protected areas (PAs) from 20 countries. This more geographically representative dataset shows that while PA visitation (whether measured as total or per capita visit numbers) is indeed declining in the United States and Japan, it is generally increasing elsewhere. Total visit numbers are growing in 15 of the 20 countries for which we could get data, with the median national rate of change unrelated to the national rate of population growth but negatively associated with wealth. Reasons for this reversal of growth in the richest countries are difficult to pin down with existing data, but the pattern is mirrored by trends in international tourist arrivals as a whole and so may not necessarily be caused by disaffection with nature. Irrespective of the explanation, it is clear that despite important downturns in some countries, nature-related tourism is far from declining everywhere, and may still have considerable potential both to generate funds for conservation and to shape people''s attitudes to the environment.  相似文献   
947.
Studies of urban wildlife are important because they can give us insight into both how animals adapt to novel environments and how some species survive and prosper in human‐dominated landscapes. Urban zoological institutions provide an ideal setting for research on such species. We report on a study of the behavior and ecology of opossums (Didelphis virginiana) on the grounds of the St. Louis Zoological Park. We used radio tracking to investigate the movement patterns and den site use of opossums on the grounds of the zoo and compared the results to data available for opossums elsewhere. We find that urban opossums in the St. Louis zoo have smaller home ranges and move shorter distances than their rural counterparts. We suggest that increased food availability and decreased risk of predation might explain such differences, and we suspect that conditions are even more favorable to opossums in a zoological setting than in cities in general. Our findings illustrate that there is much to be learned from scientific study of the free‐living animals found on zoological park grounds. Zoo Biol 00:1–17, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   
948.
A field experiment was done to quantify the mortality of fish released during a recreational angling tournament in Botany Bay, Australia. Participating boat-based anglers were divided into two groups, each representing different typical catch-and-release events. The first group (termed the ‘live weigh-in group’) retained the largest two individuals of 4 species (dusky flathead, Platycephalus fuscus, yellowfin bream, Acanthopagrus australis, sand whiting, Sillago ciliata, and trevally, Pseudocaranx dentex) in onboard holding tanks and then presented these to researchers at designated weigh-in times and stations. Gear, operational and handling data were collected before 125 fish were tagged using plastic t-bar tags, returned to the anglers and then released into two sea cages. The second group (termed the ‘immediate-release group’) immediately released 224 fish into two sea cages, after they were tagged and relevant data recorded by onboard observers. This group represented those fish routinely discarded (i) as part of catch-and-immediate-release tournaments and/or (ii) due to minimum legal sizes and/or personal quotas. Appropriate species and numbers of ‘control’ fish were seined and placed into two sea cages. All fish were monitored for mortalities over 10 days. Dusky flathead, yellowfin bream, trevally and snapper, Pagrus auratus accounted for more than 85% of the total catch. Their adjusted mortalities ranged between 0% and 36.6%. Irrespective of the treatment, most yellowfin bream and snapper deaths occurred within 3 h of being hooked and released into the cages, while trevally and dusky flathead showed a delayed mortality over 4 days. Owing to confounding effects due to their confinement, dusky flathead were excluded from further analyses. Anatomical hook location and the time between capture and release were significant predictors of mortality for yellowfin bream and trevally, respectively (p < 0.01), but none of the various gear, operational or handling factors examined were significant for snapper (p > 0.05). The results are discussed in terms of species-specific variabilities in mortalities, their causal effects and better management of catch-and-release events.  相似文献   
949.
950.
Currently, there is a lack of knowledge about GHG emissions, specifically N2O and CH4, in subtropical coastal freshwater wetland and mangroves in the southern hemisphere. In this study, we quantified the gas fluxes and substrate availability in a subtropical coastal wetland off the coast of southeast Queensland, Australia over a complete wet-dry seasonal cycle. Sites were selected along a salinity gradient ranging from marine (34 psu) in a mangrove forest to freshwater (0.05 psu) wetland, encompassing the range of tidal influence. Fluxes were quantified for CH4 (range ?0.4–483 mg C–CH4 h?1 m?2) and N2O (?5.5–126.4 μg N–N2O h?1 m?2), with the system acting as an overall source for CH4 and N2O (mean N2O and CH4 fluxes: 52.8 μg N–N2O h?1 m?2 and 48.7 mg C–CH4 h?1 m?2, respectively). Significantly higher N2O fluxes were measured during the summer months (summer mean 64.2 ± 22.2 μg N–N2O h?1 m?2; winter mean 33.1 ± 24.4 µg N–N2O h–1 m?2) but not CH4 fluxes (summer mean 30.2 ± 81.1 mg C–CH4 h?1 m?2; winter mean 37.4 ± 79.6 mg C–CH4 h?1 m?2). The changes with season are primarily driven by temperature and precipitation controls on the dissolved inorganic nitrogen (DIN) concentration. A significant spatial pattern was observed based on location within the study site, with highest fluxes observed in the freshwater tidal wetland and decreasing through the mangrove forest. The dissolved organic carbon (DOC) varied throughout the landscape and was correlated with higher CH4 fluxes, but this was a nonlinear trend. DIN availability was dominated by N–NH4 and correlated to changes in N2O fluxes throughout the landscape. Overall, we did not observe linear relationships between CH4 and N2O fluxes and salinity, oxygen or substrate availability along the fresh-marine continuum, suggesting that this ecosystem is a mosaic of processes and responses to environmental changes.  相似文献   
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