28 research outputs found

    Conodonts from the Marathon basin, Brewster County, Texas

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    Conodonts were discovered in the limestones of the Marathon region in the Big Bend country, Brewster County, Texas, as a result of field work during the summer of 1939. This was not the first known occurrence of these fossils from this region, however, as King earlier mentioned the occurrence of conodonts in siliceous shales of Devonian age. The discovery of conodonts in the Ordovician and Pennsylvanian limestones of the area had its inception in the attempt to determine whether the Dimple limestone (lower Pennsylvanian) or Maravillas limestone (upper Ordovician) was involved in a fault that was being mapped. These limestones are similar lithologically and the nature of the outcrop along the fault trace was such that the age relations of the limestone involved could not be determined...The stratigraphic distribution, systematic descriptions, and illustrations of conodonts of Ordovician and Pennsylvanian age from the Marathon region form the basis of this thesis. In some instances, such as the occurrence in the dimple formation, conodonts are the only positively identifiable fossils found in the rocks and, for this reason, have special significance in determining the age of these beds. The Ordovician conodont faunas are of importance because the occurrence in this region extends their known geographic and geologic range --Introduction, pages [1]-3

    TRY plant trait database – enhanced coverage and open access

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    Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

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    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    Under the mountain:basic training, individuality, & comradeship

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    This paper addresses questions of friendship and political community by investigating a particular complex case, comradeship in the life of the soldier. Close attention to soldiers’ accounts of their own lives, successes and failures shows that the relationship of friendship to comradeship, and of both to the success of the soldier’s individual and communal life, is complex and tense. I focus on autobiographical accounts of basic training in order to describe, and to explore the tensions between, two positions: (1) Becoming a soldier is a corrupting loss of individuality and moral sensitivity, and friendship is resistance to it. (2) Becoming a soldier is one form of flourishing, and comradeship—the soldier’s distinctive form of friendship—is one of its constitutive virtues. I draw particularly on George Orwell’s account of basic training and fighting in the Spanish Civil War, and on Tim O’Brien’s account of basic training and fighting in Vietnam
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