35 research outputs found

    The Alaska Arctic Vegetation Archive (AVA-AK)

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    The Alaska Arctic Vegetation Archive (AVA-AK, GIVD-ID: NA-US-014) is a free, publically available database archive of vegetation-plot data from the Arctic tundra region of northern Alaska. The archive currently contains 24 datasets with 3,026 non-overlapping plots. Of these, 74% have geolocation data with 25-m or better precision. Species cover data and header data are stored in a Turboveg database. A standardized Pan Arctic Species List provides a consistent nomenclature for vascular plants, bryophytes, and lichens in the archive. A web-based online Alaska Arctic Geoecological Atlas (AGA-AK) allows viewing and downloading the species data in a variety of formats, and provides access to a wide variety of ancillary data. We conducted a preliminary cluster analysis of the first 16 datasets (1,613 plots) to examine how the spectrum of derived clusters is related to the suite of datasets, habitat types, and environmental gradients. Here, we present the contents of the archive, assess its strengths and weaknesses, and provide three supplementary files that include the data dictionary, a list of habitat types, an overview of the datasets, and details of the cluster analysis

    CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey

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    The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) is designed to document the first third of galactic evolution, over the approximate redshift (z) range 8--1.5. It will image >250,000 distant galaxies using three separate cameras on the Hubble Space Telescope, from the mid-ultraviolet to the near-infrared, and will find and measure Type Ia supernovae at z>1.5 to test their accuracy as standardizable candles for cosmology. Five premier multi-wavelength sky regions are selected, each with extensive ancillary data. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to a stellar mass of 10^9 M_\odot to z \approx 2, reaching the knee of the ultraviolet luminosity function (UVLF) of galaxies to z \approx 8. The survey covers approximately 800 arcmin^2 and is divided into two parts. The CANDELS/Deep survey (5\sigma\ point-source limit H=27.7 mag) covers \sim 125 arcmin^2 within GOODS-N and GOODS-S. The CANDELS/Wide survey includes GOODS and three additional fields (EGS, COSMOS, and UDS) and covers the full area to a 5\sigma\ point-source limit of H \gtrsim 27.0 mag. Together with the Hubble Ultra Deep Fields, the strategy creates a three-tiered "wedding cake" approach that has proven efficient for extragalactic surveys. Data from the survey are nonproprietary and are useful for a wide variety of science investigations. In this paper, we describe the basic motivations for the survey, the CANDELS team science goals and the resulting observational requirements, the field selection and geometry, and the observing design. The Hubble data processing and products are described in a companion paper.Comment: Submitted to Astrophysical Journal Supplement Series; Revised version, subsequent to referee repor

    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

    The trinucleotide repeat sequence d(GTC) 15

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    Mutations Disrupting Selenocysteine Formation Cause Progressive Cerebello-Cerebral Atrophy

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    The essential micronutrient selenium is found in proteins as selenocysteine (Sec), the only genetically encoded amino acid whose biosynthesis occurs on its cognate tRNA in humans. In the final step of selenocysteine formation, the essential enzyme SepSecS catalyzes the conversion of Sep-tRNA to Sec-tRNA. We demonstrate that SepSecS mutations cause autosomal-recessive progressive cerebellocerebral atrophy (PCCA) in Jews of Iraqi and Moroccan ancestry. Both founder mutations, common in these two populations, disrupt the sole route to the biosynthesis of the 21st amino acid, Sec, and thus to the generation of selenoproteins in humans

    Prev Chronic Dis

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    IntroductionHealth-risk behaviors such as eating poorly, being physically inactive, and smoking contribute to the leading causes of morbidity and mortality in the United States and are often established during adolescence and young adulthood. The objectives of this study were to characterize the health-risk behaviors of young adults (aged 18\u201324 years) using a large population-based survey of Americans and to determine if behaviors of this group differ by weight category, as assessed by body mass index (BMI).MethodsPrevalence estimates for selected health-risk behaviors were calculated for respondents aged 18 to 24 years to the 2003 Behavioral Risk Factor Surveillance System (BRFSS). Respondents were categorized by BMI, and comparisons between sex and race and ethnicity were made within the overweight and obese categories.ResultsMore than three quarters (78.4%) of respondents consumed fewer than five fruits and vegetables per day, 43.2% reported insufficient or no physical activity, 28.9% were current smokers, 30.1% reported binge drinking, and 11.9% reported frequent mental distress. One quarter (26.1%) of respondents were overweight, and 13.6% were obese. Of obese young adults, 67.2% reported that they currently were trying to lose weight; however, only 24.3% reported having received professional advice to lose weight. More obese women (34.2%) than obese men (16.7%) reported having received professional advice to lose weight. Only 19.1% of obese non-Hispanic white respondents had received professional advice to lose weight compared with 28.0% of obese Hispanic respondents and 30.6% of obese non-Hispanic black respondents.ConclusionMany young adults engage in unhealthy behaviors, and differences exist in health-risk behaviors by BMI category and specifically by sex and race and ethnicity within BMI categories. The transition from adolescence to adulthood may be an opportune time for intervening to prevent future chronic disease.2007720
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