1,721,015 research outputs found
Spatial Variation in the Integrated Assessment of Pasture Dynamics and Soil Health on the North Wyke Farm Platform
No full textThis dataset contains measurements made in fields on the North Wyke Farm Platform, a national capability in South West England. These fields contained either permanent pasture or a Lolium perenne and Trifolium repens pasture, and were used as part of a beef and sheep livestock system. 10 locations were chosen in each field, 5 within 50 m of the field boundary and 5 closer to the middle of the field, and the latitude and longitude of each point is provided. At each location a range of measurements were made, including: percentage cover of plants and bare ground; leaf dry matter content; specific leaf area; pasture dry matter by rising plate meter; soil bulk density; soil organic matter; soil structure; earthworm counts and weights for different functional groups; and soil penetrometer readings
The effect of soil type on yield and macro- and micronutrient content of a wide range of pasture species
No full textThe objective of the experiment that generated this dataset was to determine the effect of soil type on the micronutrient content of pasture species (a range of grasses, legumes and forbs). The experiment was conducted in a controlled environment facility. Data are presented on the dry matter yield of each species and the concentration of 21 elements measured in the herbage (Al, As, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Mi, P, Pb, S, Se, Ti, Zn and I). Data are also presented on the total and extractable concentration of elements in the soil, as well as details of nutrient/fertilizer addition and experimental design
Elemental concentrations and growth of wild-type and cultivated pasture species
No full textThe objective of the experiment that generated this dataset was to determine how pasture species (grasses, legumes and forbs) differ in their macro- and micronutrients concentrations and growth traits. Cultivated and wild-type varieties of species were grown as it was hypothesised that breeding of cultivated varieties that respond well to inorganic NPK fertilizers may have resulted in plants that have fewer traits that enable them to acquire other macro- and micronutrients from soil.
Data includes:
• Plant yield
• Macro- and micronutrient concentrations (and some potentially toxic elements): Al, As, Ca, Cd, Co, Cr, Cu, Fe, I, K, Mg, Mn, Mo, Na, Mi, P, Pb, S, Se, Ti, and Zn. Note that nitrogen was not measured.
• Plant traits: leaf mass, root mass, aboveground dry weight, leaf area.
• Growing medium total and extractable element concentrations, plus pH and cation exchange capacity
Water chemistry of surface and subsurface runoff from agricultural grasslands
No full textThis dataset comprises a number of measurements of water chemistry and water quality taken from the North Wyke Farm Platform (NWFP, Devon, UK) between October 2012 and April 2018. The dataset is an amalgamation of data from a number of experimental campaigns, where water samples from the combined surface and subsurface runoff from hydrologically isolated fields under different pasture types were collected and analysed in the laboratory for water quality measurements. These measurements include dissolved total organic carbon and non-purgeable organic carbon; ammonium, total nitrogen and total oxidisable nitrogen; total and reactive phosphorus; and suspended sediment. Note that this is not a continuous dataset and that not all studies measured the same parameters. Information on sample numbers, dates and laboratory water quality measurements made are given in Summary_of_available_data.csv.
The NWFP measures water quality parameters in-situ at water flumes for each of its 15 catchments, in addition to water discharge rate. Environmental measurements such as precipitation and soil moisture at each catchment’s centre are also measured. In-situ flume measurements have been taken at 15-minute intervals continuously since 2012 and are openly available via the NWFP data portal. Such in-situ (proxy) measurements deemed to be most complementary to the laboratory measurements are also provided in the amalgamated dataset, at the 15-minute interval closest to the physical collection of the water for laboratory analysis. Further data and background information are available online, see the related outputs for more information. It is anticipated that this dataset may be used to compare in-situ proxies with laboratory measurements (for example, turbidity and suspended sediment) or for the comparison of in-situ and laboratory measurements of the same analyte
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Simplified method for microlitre deuterium measurements in water and urine by gas chromatography-higth-temperature conversion-isotoperatio mass spectrometry.
No full textAbstract
Deuterium (2H) in water and urine can be measured by off-line and, more recently, on-line techniques using isotope ratio mass spectrometry (IRMS). We describe a new simple on-line pyrolysis method for the analysis of 2H/1H in water and urine samples by continuous flow IRMS, normally used for 2H/1H measurements in organic compounds. A deactivated column connected the split injector to a high-temperature conversion reactor (TC HD), and 0.5 microL of sample was injected. Accuracy and precision were determined with Vienna Standard Mean Ocean Water (VSMOW), Standard Light Antarctic Precipitation (SLAP), and Greenland Ice Sheet Precipitation (GISP). The range of linearity was measured with a calibration curve of enriched water from 0 up to 0.1 atom percent excess (APE) (i.e. -72 up to 6323 delta per mil (deltaD per thousand)) with a precision of <5 per thousand and accuracy ranging between 1 and 55 per thousand. Blinded reanalysis of urine samples by an equilibration device (Gas Bench) and by a dedicated pyrolysis system (TC/EA) was performed and results compared by the Bland-Altman test. Enrichments ranged between 600 and 2400 per thousand deltaD(VSMOW) with a precision of +/-5 per thousand. Urine enrichments described by our method were strongly correlated with values obtained by Gas Bench and TC/EA (p < 0.0001). There was a significant memory effect that was reduced by injecting the sample 15 times and discarding the first 10 injections, together with accurate furnace conditioning and appropriate cleaning of the syringe. Data indicate that the method is accurate, and that it can be used for water and urine deuterium determination when a Gas Bench or TC/EA instrument is not available and the amount of sample is limited
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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