Publications by authors named "Steven Slater"

In the United States, the Bald and Golden Eagle Protection Act prohibits take of golden eagles (Aquila chrysaetos) unless authorized by permit, and stipulates that all permitted take must be sustainable. Golden eagles are unintentionally killed in conjunction with many lawful activities (e.g.

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Diadromy affords fish access to productive ecosystems, increasing growth and ultimately fitness, but it is unclear whether these advantages persist for species migrating within highly altered habitat. Here, we compared the foraging success of wild Delta Smelt-an endangered, zooplanktivorous, annual, semi-anadromous fish that is endemic to the highly altered San Francisco Estuary (SFE)-collected from freshwater (<0.55 psu) and brackish habitat (≥0.

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The abundance of Delta Smelt (Hypomesus transpacificus), a fish species endemic to the upper San Francisco Estuary (SFE), is declining. Several causes for the population decline have been proposed, including food limitation and contaminant effects. Here, using juvenile Delta Smelt collected from throughout their range, we measured a suite of indices across three levels of biological organization (cellular, organ, individual) that reflect fish condition at temporal scales ranging from hours to weeks.

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Exotic invasive species can directly and indirectly influence natural ecological communities. Cheatgrass (Bromus tectorum) is non-native to the western United States and has invaded large areas of the Great Basin. Changes to the structure and composition of plant communities invaded by cheatgrass likely have effects at higher trophic levels.

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Porcine epidemic diarrhea virus (PEDV) has emerged in Vietnam since 2009. Herein, full-length genome sequences are reported for three PEDV isolates from pigs displaying severe diarrhea from farms located in northern and southern provinces of Vietnam. The results provide more understanding of the molecular characteristics of PEDV in Vietnam.

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Studying rare and sensitive species is a challenge in conservation biology. The problem is exemplified by the case of the imperiled delta smelt Hypomesus transpacificus, a small delicate fish species endemic to the San Francisco Estuary, California. Persistent record-low levels of abundance and relatively high sensitivity to handling stress pose considerable challenges to studying delta smelt in the wild.

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Two groups independently sequenced the Agrobacterium tumefaciens C58 genome in 2001. We report here consolidation of these sequences, updated annotation, and additional analysis of the evolutionary history of the linear chromosome, which is apparently limited to the biovar I group of Agrobacterium.

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Xenorhabdus bovienii (SS-2004) bacteria reside in the intestine of the infective-juvenile (IJ) stage of the entomopathogenic nematode, Steinernema jollieti. The recent sequencing of the X. bovienii genome facilitates its use as a model to understand host - symbiont interactions.

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Members of the genus Xenorhabdus are entomopathogenic bacteria that associate with nematodes. The nematode-bacteria pair infects and kills insects, with both partners contributing to insect pathogenesis and the bacteria providing nutrition to the nematode from available insect-derived nutrients. The nematode provides the bacteria with protection from predators, access to nutrients, and a mechanism of dispersal.

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Leaf-cutter ants are one of the most important herbivorous insects in the Neotropics, harvesting vast quantities of fresh leaf material. The ants use leaves to cultivate a fungus that serves as the colony's primary food source. This obligate ant-fungus mutualism is one of the few occurrences of farming by non-humans and likely facilitated the formation of their massive colonies.

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Herbivores can gain indirect access to recalcitrant carbon present in plant cell walls through symbiotic associations with lignocellulolytic microbes. A paradigmatic example is the leaf-cutter ant (Tribe: Attini), which uses fresh leaves to cultivate a fungus for food in specialized gardens. Using a combination of sugar composition analyses, metagenomics, and whole-genome sequencing, we reveal that the fungus garden microbiome of leaf-cutter ants is composed of a diverse community of bacteria with high plant biomass-degrading capacity.

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The family Rhizobiaceae contains plant-associated bacteria with critical roles in ecology and agriculture. Within this family, many Rhizobium and Sinorhizobium strains are nitrogen-fixing plant mutualists, while many strains designated as Agrobacterium are plant pathogens. These contrasting lifestyles are primarily dependent on the transmissible plasmids each strain harbors.

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Although organisms with linear chromosomes must solve the problem of fully replicating their chromosome ends, this chromosome configuration has emerged repeatedly during bacterial evolution and is evident in three divergent bacterial phyla. The benefit usually ascribed to this topology is the ability to boost genetic variation through increased recombination. But because numerous processes can impact linkage disequilibrium, such an effect is difficult to assess by comparing across bacterial taxa that possess different chromosome topologies.

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Background: In sequencing the genomes of two Xenorhabdus species, we encountered a large number of sequence repeats and assembly anomalies that stalled finishing efforts. This included a stretch of about 12 Kb that is over 99.9% identical between the plasmid and chromosome of X.

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Transgenic plants are potentially valuable systems for the large scale manufacture of therapeutic proteins. To improve this technology, determining the importance of transgene transcript levels on protein accumulation in sink tissues during their development is crucial. In transgenic maize (Zea mays L.

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Tocopherols are important antioxidants in lipophilic environments. They are synthesized by plants and some photosynthetic bacteria. Recent efforts to analyze and engineer tocopherol biosynthesis led to the identification of Synechocystis sp.

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The multicellular developmental cycle of Myxococcus xanthus requires large-scale changes in gene transcription, and recent findings indicate that NtrC-like activators play a prominent role in regulating these changes. In this study, we made insertions in 28 uncharacterized ntrC-like activator (nla) genes and found that eight of these insertions cause developmental defects. Hence, these results are consistent with the idea that M.

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