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The evolution, approval and implementation of the U.S. Geological Survey Science Data Lifecycle Model
This paper details how the United States Geological Survey (USGS) Community for Data Integration (CDI) Data Management Working Group developed a Science Data Lifecycle Model, and the role the Model plays in shaping agency-wide policies. Starting with an extensive literature review of existing data Lifecycle models, representatives from various backgrounds in USGS attended a two-day meeting where the basic elements for the Science Data Lifecycle Model were determined. Refinements and reviews spanned two years, leading to finalization of the model and documentation in a formal agency publication . The Model serves as a critical framework for data management policy, instructional resources, and tools. The Model helps the USGS address both the Office of Science and Technology Policy (OSTP) for increased public access to federally funded research, and the Office of Management and Budget (OMB) 2013 Open Data directives, as the foundation for a series of agency policies related to data management planning, metadata development, data release procedures, and the long-term preservation of data. Additionally, the agency website devoted to data management instruction and best practices (www2.usgs.gov/datamanagement) is designed around the Model’s structure and concepts. This paper also illustrates how the Model is being used to develop tools for supporting USGS research and data management processes.
Molecular evolution of TRPC4 regulatory sequences supports a role in mammalian thermoregulatory adaptation
Background Proteins encoded by the canonical transient receptor potential (Trpc) gene family form transmembrane channels involved in diverse signal-transduction pathways. Trpc4 has been shown necessary for the induction of nonshivering thermogenesis (NST) in mice, a key component of which is thermogenic brown adipose tissue (BAT). In bats, T rpc4 exhibited diversifying selection within exons encoding regulatory binding sites of TRPC4. Methods To assess whether diversification of these regulatory sequences mirrors the diversification of mammalian thermoregulatory strategies, the ratio of nonsynonymous to synonymous substitutions (ω) was estimated for multiple tetrapod outgroups and eutherian orders. Four questions were addressed: (1) Did the ancestral eutherian Trpc4 diverge under positive selection from nonplacental mammals that lack BAT? (2) Did Trpc4 subsequently become more constrained in descendant eutherian clades? (3) In eutherian clades that subsequently lost BAT by inactivation of the thermogenin gene Ucp1 , did Trpc4 become less constrained? (4) Does the evolutionary rate of Trpc4 differ between quantitatively more heterothermic mammal orders (bats and rodents) relative to quantitatively less heterothermic outgroups (carnivores, artiodactylids, and primates)? Results Coincident with the advent of BAT, Trpc4 evolutionary rate increased significantly in ancestral eutheria after their divergence from nonplacental mammals but a branch-site model did not support a rate class ω > 1 along that branch. In descendant eutherian mammals, Trpc4 became far more constrained, with an evolutionary rate less than half that of tetrapod clades lacking NST, a pattern was not seen in other Trp channel genes. Intensifying selection in descendent eutherian mammals was further supported with the RELAX program, which also indicated reduced constraint on Trpc4 in clades that have secondarily lost BAT. However, no consistent pattern was identified within mammalian orders with strong variation in heterothermy: evidence of increased evolutionary rate was again found in bats for Trpc4 as well as homologs it directly binds in heteromeric membrane channels ( Trpc5 and Trpc1 ), yet all rodent Trpc genes had low evolutionary rates. Evolutionary rates of Trpc4 and Trpc1 in bats were consistent with relaxed constraint whereas bat Trpc5 experienced diversifying selection. Most variation among tetrapod TRPC4 sequences lies within an 85 amino-acid window that is functionally uncharacterized. Sequence alignments demonstrated that the TRPC4 β isoform, which lacks a portion of the C-terminal regulatory region, originated in basal eutherians but appears to be lost in many tip lineages. Collectively, the data indicate that the C-terminal region of TRPC4 has responded to selection on NST thermoregulation during the diversification of eutherian mammals. The drivers of increased diversification of Trpc4 and interacting genes in bats remain to be determined.
Genomic evolution, recombination, and inter-strain diversity of chelonid alphaherpesvirus 5 from Florida and Hawaii green sea turtles with fibropapillomatosis
Chelonid alphaherpesvirus 5 (ChHV5) is a herpesvirus associated with fibropapillomatosis (FP) in sea turtles worldwide. Single-locus typing has previously shown differentiation between Atlantic and Pacific strains of this virus, with low variation within each geographic clade. However, a lack of multi-locus genomic sequence data hinders understanding of the rate and mechanisms of ChHV5 evolutionary divergence, as well as how these genomic changes may contribute to differences in disease manifestation. To assess genomic variation in ChHV5 among five Hawaii and three Florida green sea turtles, we used high-throughput short-read sequencing of long-range PCR products amplified from tumor tissue using primers designed from the single available ChHV5 reference genome from a Hawaii green sea turtle. This strategy recovered sequence data from both geographic regions for approximately 75% of the predicted ChHV5 coding sequences. The average nucleotide divergence between geographic populations was 1.5%; most of the substitutions were fixed differences between regions. Protein divergence was generally low (average 0.08%), and ranged between 0 and 5.3%. Several atypical genes originally identified and annotated in the reference genome were confirmed in ChHV5 genomes from both geographic locations. Unambiguous recombination events between geographic regions were identified, and clustering of private alleles suggests the prevalence of recombination in the evolutionary history of ChHV5. This study significantly increased the amount of sequence data available from ChHV5 strains, enabling informed selection of loci for future population genetic and natural history studies, and suggesting the (possibly latent) co-infection of individuals by well-differentiated geographic variants.
Assimilating models and data to enhance predictions of shoreline evolution
A modeling system that considers both long- and short-term process-driven shoreline change is presented. The modeling system is integrated into a data assimilation framework that uses sparse observations of shoreline change to correct a model forecast and to determine unobserved model variables and free parameters. Application of the assimilation algorithm also provides quantitative statistical estimates of uncertainty that can be applied to coastal hazard and vulnerability assessments. Significant attention is given to the estimation of four non-observable quantities using the data assimilation framework that utilizes only one observable process (i.e. ,shoreline change). The general framework discussed here can be applied to many other geophysical processes by simply changing the model component to one applicable to the processes of interest.
Evolution of the rump region in the golden-rumped elephant shrew
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The evolution of National Park Service fire policy
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Phylogeography of the night lizard, Xantusia henshawi, in southern California: Evolution across fault zones
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Morphological and genetic evolution appear decoupled in Pacific skinks (Squamata: Scincidae: Emoia)
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Evolution and management of the North-American grasslands herpetofauna
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The evolution of National Park Service fire policy
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Estuarine Shores: Evolution, Environments and Human Alterations
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Karyotypic variation in oryzomyine rodents (Cricetinae) with comments on chromosomal evolution in the neotropical cricetine complex
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Terrestrial vertebrates of tidal marshes: evolution, ecology, and conservation
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Evolution of lek social systems in manakins: alternative models and proofs
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Adaptive harvest management of waterfowl: implementation and evolution
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Visitor impact assessment and monitoring systems: Evolution and current development
Managers of protected areas are increasingly concerned with recreation impacts to the resource and how they should be managed. Impact management programs must be based on information about the severity and extent of impacts and how they are changing over time. This information need has generated considerable interest in the development of visitor impact assessment and monitoring (VIAM) systems. Over the past three decades VIAM systems have been implemented in various protected areas. This paper provides a historical review of VIAM systems and discusses the current areas of refinement in their methodology. Potential areas of future research are also outlined.
Evolution and biogeography of Mexican small-eared shrews of the Cryptotis mexicana-group (Insectivora: Soricidae)
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