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1.
Am J Bot ; 104(6): 891-904, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28634257

RESUMO

PREMISE OF THE STUDY: The capsular-fruited genus Metrosideros (Myrtaceae) is one of the most widely distributed flowering plant genera in the Pacific but is extinct in Australia today. The center of geographic origin for the genus and the reason for and timing of its extinction in Australia remain uncertain. We identify fossil Metrosideros fruits from the newly discovered Golden Fleece fossil flora in the Oligo-Miocene of Tasmania, Australia, shedding further light on these problems. METHODS: Standard paleopalynological techniques were used to date the fossil-bearing sediments. Scanning electron microscopy and an auto-montage camera system were used to take high-resolution images of fossil and extant fruits taken from herbarium specimens. Fossils are identified using a nearest-living-relative approach. KEY RESULTS: The fossil-bearing sediments are palynostratigraphically dated as being Proteacidites tuberculatus Zone Equivalent (ca. 33-16 Ma) in age and provide a confident Oligo-Miocene age for the macrofossils. Two new fossil species of Metrosideros are described and are here named Metrosideros dawsonii sp. nov. and Metrosideros wrightii sp. nov. CONCLUSIONS: These newly described fossil species of Metrosideros provide a second record of the genus in the Cenozoic of Australia, placing them in the late Early Oligocene to late Early Miocene. It is now apparent not only that Metrosideros was present in Australia, where the genus is now extinct, but that at least several Metrosideros species were present during the Cenozoic. These fossils further strengthen the case for an Australian origin of the genus.


Assuntos
Myrtaceae/classificação , Filogenia , Fósseis , Frutas , Tasmânia
2.
J Community Health ; 41(4): 772-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26831485

RESUMO

The barbershop has been used to target African American (AA) men across age groups for health screenings, health interventions, and for research. However, few studies explore the sociodemographic characteristics of barbers and their clients. Additionally, few have evaluated the client's relative comfort with receiving health information and screenings in barbershops and other non-clinical settings. Lastly, it is unknown whether barbers feel capable of influencing health-decision making of AA men. AA male clients and barbers completed a self-administered survey in barbershops in predominantly AA neighborhoods throughout Chicago, Illinois. We assessed sociodemographic characteristics and attitudes towards receiving physical and mental health education and screenings in barbershops and other settings. Barbers were also surveyed regarding their most and least common clients by age group and their perceived ability to influence the decision-making of AA males by age group. AAs surveyed in barbershops have similar rates of high school completion, poverty and unemployment as the AA residents of their neighborhood. AA males prefer to receive health education and screening in clinician offices followed by barbershops and churches. Barbers reported serving males age 18-39 years of age most frequently while men 50 years and older were the least served group. Overall, barbers did not believe they could influence the decision-making of AA men and in the best case scenario, only 33 % felt they could influence young men 18-29 years old. Barbershops reach AA men that are representative of the demographics of the neighborhood where the barbershop is located. Barbers reach a small population of men over age 49 and feel incapable of influencing the decisions of AAs over age 39. Further studies are needed to assess other locales for accessing older AA men and to evaluate the feasibility of mental health interventions and screenings within the barbershop.


Assuntos
Barbearia , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Conhecimentos, Atitudes e Prática em Saúde , Promoção da Saúde/métodos , Adolescente , Adulto , Idoso , Chicago , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Modelos Psicológicos , Inquéritos e Questionários , Adulto Jovem
3.
BMC Bioinformatics ; 14: 158, 2013 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-23668630

RESUMO

BACKGROUND: Scientists rarely reuse expert knowledge of phylogeny, in spite of years of effort to assemble a great "Tree of Life" (ToL). A notable exception involves the use of Phylomatic, which provides tools to generate custom phylogenies from a large, pre-computed, expert phylogeny of plant taxa. This suggests great potential for a more generalized system that, starting with a query consisting of a list of any known species, would rectify non-standard names, identify expert phylogenies containing the implicated taxa, prune away unneeded parts, and supply branch lengths and annotations, resulting in a custom phylogeny suited to the user's needs. Such a system could become a sustainable community resource if implemented as a distributed system of loosely coupled parts that interact through clearly defined interfaces. RESULTS: With the aim of building such a "phylotastic" system, the NESCent Hackathons, Interoperability, Phylogenies (HIP) working group recruited 2 dozen scientist-programmers to a weeklong programming hackathon in June 2012. During the hackathon (and a three-month follow-up period), 5 teams produced designs, implementations, documentation, presentations, and tests including: (1) a generalized scheme for integrating components; (2) proof-of-concept pruners and controllers; (3) a meta-API for taxonomic name resolution services; (4) a system for storing, finding, and retrieving phylogenies using semantic web technologies for data exchange, storage, and querying; (5) an innovative new service, DateLife.org, which synthesizes pre-computed, time-calibrated phylogenies to assign ages to nodes; and (6) demonstration projects. These outcomes are accessible via a public code repository (GitHub.com), a website (http://www.phylotastic.org), and a server image. CONCLUSIONS: Approximately 9 person-months of effort (centered on a software development hackathon) resulted in the design and implementation of proof-of-concept software for 4 core phylotastic components, 3 controllers, and 3 end-user demonstration tools. While these products have substantial limitations, they suggest considerable potential for a distributed system that makes phylogenetic knowledge readily accessible in computable form. Widespread use of phylotastic systems will create an electronic marketplace for sharing phylogenetic knowledge that will spur innovation in other areas of the ToL enterprise, such as annotation of sources and methods and third-party methods of quality assessment.


Assuntos
Filogenia , Software , Internet
4.
New Phytol ; 199(2): 559-570, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23647069

RESUMO

The processes by which the functions of interdependent tissues are coordinated as lineages diversify are poorly understood. Here, we examine evolutionary coordination of vascular, epidermal and cortical leaf tissues in the anatomically, ecologically and morphologically diverse woody plant family Proteaceae. We found that, across the phylogenetic range of Proteaceae, the sizes of guard, epidermal, palisade and xylem cells were positively correlated with each other but negatively associated with vein and stomatal densities. The link between venation and stomata resulted in a highly efficient match between potential maximum water loss (determined by stomatal conductance) and the leaf vascular system's capacity to replace that water. This important linkage is likely to be driven by stomatal size, because spatial limits in the packing of stomata onto the leaf surface apparently constrain the maximum size and density of stomata. We conclude that unified evolutionary changes in cell sizes of independent tissues, possibly mediated by changes in genome size, provide a means of substantially modifying leaf function while maintaining important functional links between leaf tissues. Our data also imply the presence of alternative evolutionary strategies involving cellular miniaturization during radiation into closed forest, and cell size increase in open habitats.


Assuntos
Tamanho Celular , Folhas de Planta/citologia , Evolução Biológica , Ecossistema , Modelos Biológicos , Filogenia , Folhas de Planta/anatomia & histologia , Estômatos de Plantas/citologia , Feixe Vascular de Plantas/anatomia & histologia , Feixe Vascular de Plantas/citologia , Proteaceae/citologia , Característica Quantitativa Herdável , Especificidade da Espécie
5.
Funct Plant Biol ; 46(3): 286-293, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-32172771

RESUMO

Understanding intraspecific variation in the vulnerability of the xylem to hydraulic failure during drought is critical in predicting the response of forest tree species to climate change. However, few studies have assessed intraspecific variation in this trait, and a likely limitation is the large number of measurements required to generate the standard 'vulnerability curve' used to assess hydraulic failure. Here we explore an alternative approach that requires fewer measurements, and assess within species variation in leaf xylem vulnerability in Eucalyptus globulus Labill., an ecologically and economically important species with known genetic variation in drought tolerance. Using this approach we demonstrate significant phenotypic differences and evidence of plasticity among two provenances with contrasting drought tolerance.


Assuntos
Secas , Eucalyptus , Folhas de Planta , Árvores , Xilema
6.
PLoS One ; 8(12): e84378, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24358359

RESUMO

Ecological theory differentiates rainforest and open vegetation in many regions as functionally divergent alternative stable states with transitional (ecotonal) vegetation between the two forming transient unstable states. This transitional vegetation is of considerable significance, not only as a test case for theories of vegetation dynamics, but also because this type of vegetation is of major economic importance, and is home to a suite of species of conservation significance, including the world's tallest flowering plants. We therefore created predictions of patterns in plant functional traits that would test the alternative stable states model of these systems. We measured functional traits of 128 trees and shrubs across tropical and temperate rainforest - open vegetation transitions in Australia, with giant eucalypt forests situated between these vegetation types. We analysed a set of functional traits: leaf carbon isotopes, leaf area, leaf mass per area, leaf slenderness, wood density, maximum height and bark thickness, using univariate and multivariate methods. For most traits, giant eucalypt forest was similar to rainforest, while rainforest, particularly tropical rainforest, was significantly different from the open vegetation. In multivariate analyses, tropical and temperate rainforest diverged functionally, and both segregated from open vegetation. Furthermore, the giant eucalypt forests overlapped in function with their respective rainforests. The two types of giant eucalypt forests also exhibited greater overall functional similarity to each other than to any of the open vegetation types. We conclude that tropical and temperate giant eucalypt forests are ecologically and functionally convergent. The lack of clear functional differentiation from rainforest suggests that giant eucalypt forests are unstable states within the basin of attraction of rainforest. Our results have important implications for giant eucalypt forest management.


Assuntos
Clima , Ecossistema , Plantas , Característica Quantitativa Herdável , Árvores , Análise de Variância , Queensland
7.
Genome Res ; 17(6): 732-45, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17567993

RESUMO

For the approximately 1% of the human genome in the ENCODE regions, only about half of the transcriptionally active regions (TARs) identified with tiling microarrays correspond to annotated exons. Here we categorize this large amount of "unannotated transcription." We use a number of disparate features to classify the 6988 novel TARs-array expression profiles across cell lines and conditions, sequence composition, phylogenetic profiles (presence/absence of syntenic conservation across 17 species), and locations relative to genes. In the classification, we first filter out TARs with unusual sequence composition and those likely resulting from cross-hybridization. We then associate some of those remaining with proximal exons having correlated expression profiles. Finally, we cluster unclassified TARs into putative novel loci, based on similar expression and phylogenetic profiles. To encapsulate our classification, we construct a Database of Active Regions and Tools (DART.gersteinlab.org). DART has special facilities for rapidly handling and comparing many sets of TARs and their heterogeneous features, synchronizing across builds, and interfacing with other resources. Overall, we find that approximately 14% of the novel TARs can be associated with known genes, while approximately 21% can be clustered into approximately 200 novel loci. We observe that TARs associated with genes are enriched in the potential to form structural RNAs and many novel TAR clusters are associated with nearby promoters. To benchmark our classification, we design a set of experiments for testing the connectivity of novel TARs. Overall, we find that 18 of the 46 connections tested validate by RT-PCR and four of five sequenced PCR products confirm connectivity unambiguously.


Assuntos
Mapeamento Cromossômico , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/fisiologia , Genoma Humano/fisiologia , Locos de Características Quantitativas/genética , Transcrição Gênica/fisiologia , Sequência de Bases , Humanos , Dados de Sequência Molecular
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