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排序方式: 共有601条查询结果,搜索用时 109 毫秒
581.
David R. Thompson Kimberly T. Goetz Paul M. Sagar Leigh G. Torres Caitlin E. Kroeger Lisa A. Sztukowski Rachael A. Orben Andrew J. Hoskins Richard A. Phillips 《水产资源保护:海洋与淡水生态系统》2021,31(10):2967-2978
- The use of miniaturized electronic tracking devices has illuminated our understanding of seabird distributions and habitat use, and how anthropogenic threats interact with seabirds in both space and time. To determine the year-round distribution of adult Campbell albatross (Thalassarche impavida), a single-island endemic, breeding only at Campbell Island in New Zealand's subantarctic, a total of 68 year-long location data sets were acquired from light-based geolocation data-logging tags deployed on breeding birds in 2009 and 2010.
- During the incubation and chick-guard phases of the breeding season, birds used cool (<10°C) waters over the Campbell Plateau, but also ranged over deeper, shelf-break and oceanic waters (4,000–5,500 m) beyond the Plateau. Later in the breeding season, during post-guard chick-rearing, Campbell albatrosses exploited generally deep waters (4,000–5,000 m) beyond the Campbell Plateau.
- During the non-breeding period, adults tended to move northwards into warmer (approximately 15°C) waters and occupied areas beyond western Australia in the west to offshore from Chile in the east. Overall, about 30% of adults spent some of their non-breeding period in the central and eastern Pacific Ocean, substantially expanding the previously reported range for this species.
- One bird, that failed in its breeding attempt in October 2009, departed Campbell Island and circumnavigated the southern oceans before being recaptured back at Campbell Island in October 2010. This is the first example of an annually-breeding albatross species completing a circumnavigation between breeding attempts.
- Overlap with fishing effort, using data from the Global Fishing Watch database, was assessed on a monthly and seasonal basis. Generally, levels of overlap between Campbell albatross and fishing effort were relatively low during the breeding season but were approximately 60% higher during the non-breeding period, underlining the need for international initiatives to safeguard this species.
582.
Sabine Fromm Elena Beißwanger Annemarie Käsbohrer Bernd-Alois Tenhagen 《Preventive veterinary medicine》2014
The importance of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) as an infectious agent for humans has increased in recent years in Germany. Although it is well known that the prevalence of MRSA in pig farms is high, risk factors for the presence of MRSA in herds of fattening pigs are still poorly understood. The aim of this study was to evaluate available data from previous studies on MRSA in fattening pigs in a meta-analysis to answer the question: What are the factors associated with the occurrence of MRSA in fattening pig herds? 相似文献
583.
Bernard Tivoli Alain Baranger Carmen M. Avila Sabine Banniza Martin Barbetti Weidong Chen Jenny Davidson Kurt Lindeck Mohammed Kharrat Diego Rubiales Mohamed Sadiki Josefina C. Sillero Mark Sweetingham Fred J. Muehlbauer 《Euphytica》2006,147(1-2):223-253
Summary Necrotrophic pathogens of the cool season food legumes (pea, lentil, chickpea, faba bean and lupin) cause wide spread disease
and severe crop losses throughout the world. Environmental conditions play an important role in the development and spread
of these diseases. Form of inoculum, inoculum concentration and physiological plant growth stage all affect the degree of
infection and the amount of crop loss. Measures to control these diseases have relied on identification of resistant germplasm
and development of resistant varieties through screening in the field and in controlled environments. Procedures for screening
and scoring germplasm and breeding lines for resistance have lacked uniformity among the various programs worldwide. However,
this review highlights the most consistent screening and scoring procedures that are simple to use and provide reliable results.
Sources of resistance to the major necrotrophic fungi are summarized for each of the cool season food legumes. Marker-assisted
selection is underway for Ascochyta blight of pea, lentil and chickpea, and Phomopsis blight of lupin. Other measures such
as fungicidal control and cultural control are also reviewed. The emerging genomic information on the model legume, Medicago truncatula, which has various degrees of genetic synteny with the cool season food legumes, has promise for identification of closely
linked markers for resistance genes and possibly for eventual map-based cloning of resistance genes. Durable resistance to
the necrotrophic pathogens is a common goal of cool season food legume breeders. 相似文献
584.
Cudney-Valenzuela Sabine J. Arroyo-Rodríguez Víctor Andresen Ellen Toledo-Aceves Tarin 《Landscape Ecology》2022,37(6):1497-1507
Landscape Ecology - Biodiversity patterns depend on landscape structure, but the spatial scale at which such dependence is strongest (scale of effect, SoE) remains poorly understood, especially for... 相似文献
585.
Carminic acid, the well-known red dyestuff from cochineal insects (Dactylopius spp.), is a potent feeding deterrent to ants. This deterrency may be indicative of the natural function of the compound, which may have evolved in cochineals as a chemical weapon against predation. The behavior of an unusual predator is described-the carnivorous caterpillar of a pyralid moth (Laetilia coccidivora)-which is undeterred by carminic acid and feeds on cochineals. The animal has the remarkable habit of utilizing the ingested carminic acid for defensive purposes of its own. 相似文献
586.
Dietrich FS Voegeli S Brachat S Lerch A Gates K Steiner S Mohr C Pöhlmann R Luedi P Choi S Wing RA Flavier A Gaffney TD Philippsen P 《Science (New York, N.Y.)》2004,304(5668):304-307
We have sequenced and annotated the genome of the filamentous ascomycete Ashbya gossypii. With a size of only 9.2 megabases, encoding 4718 protein-coding genes, it is the smallest genome of a free-living eukaryote yet characterized. More than 90% of A. gossypii genes show both homology and a particular pattern of synteny with Saccharomyces cerevisiae. Analysis of this pattern revealed 300 inversions and translocations that have occurred since divergence of these two species. It also provided compelling evidence that the evolution of S. cerevisiae included a whole genome duplication or fusion of two related species and showed, through inferred ancient gene orders, which of the duplicated genes lost one copy and which retained both copies. 相似文献
587.
Hvorup RN Goetz BA Niederer M Hollenstein K Perozo E Locher KP 《Science (New York, N.Y.)》2007,317(5843):1387-1390
BtuCD is an adenosine triphosphate-binding cassette (ABC) transporter that translocates vitamin B12 from the periplasmic binding protein BtuF into the cytoplasm of Escherichia coli. The 2.6 angstrom crystal structure of a complex BtuCD-F reveals substantial conformational changes as compared with the previously reported structures of BtuCD and BtuF. The lobes of BtuF are spread apart, and B12 is displaced from the binding pocket. The transmembrane BtuC subunits reveal two distinct conformations, and the translocation pathway is closed to both sides of the membrane. Electron paramagnetic resonance spectra of spin-labeled cysteine mutants reconstituted in proteoliposomes are consistent with the conformation of BtuCD-F that was observed in the crystal structure. A comparison with BtuCD and the homologous HI1470/71 protein suggests that the structure of BtuCD-F may reflect a posttranslocation intermediate. 相似文献
588.
The oceanic sink for anthropogenic CO2 总被引:6,自引:0,他引:6
Sabine CL Feely RA Gruber N Key RM Lee K Bullister JL Wanninkhof R Wong CS Wallace DW Tilbrook B Millero FJ Peng TH Kozyr A Ono T Rios AF 《Science (New York, N.Y.)》2004,305(5682):367-371
Using inorganic carbon measurements from an international survey effort in the 1990s and a tracer-based separation technique, we estimate a global oceanic anthropogenic carbon dioxide (CO2) sink for the period from 1800 to 1994 of 118 +/- 19 petagrams of carbon. The oceanic sink accounts for approximately 48% of the total fossil-fuel and cement-manufacturing emissions, implying that the terrestrial biosphere was a net source of CO2 to the atmosphere of about 39 +/- 28 petagrams of carbon for this period. The current fraction of total anthropogenic CO2 emissions stored in the ocean appears to be about one-third of the long-term potential. 相似文献
589.
Steghaus-Kovac S 《Science (New York, N.Y.)》2002,295(5558):1212-1213
590.