1,720,972 research outputs found
Biogeochemical controls on metal distribution and pedogenesis in tropical island soils
No full textThe archived dataset was collected during a field sampling campaign conducted on Manukan Island, Sabah, Malaysia. A total of twenty-five soil samples were systematically collected from October 2008 to August 2011 across three distinct environmental domains: sandy beach (SB), vegetation-dense (VD), and high-elevation (HE) areas. Topsoil samples (0–50 cm depth) and subsoil samples (100–300 cm depth) were obtained using a hand auger, and additional coral samples from the coastline and sandstone samples (parent geological material) from nearby outcrops were also collected.
Soil samples were air-dried, pulverized, and passed through a 2-mm sieve prior to analysis. Physico-chemical parameters, including soil pH, redox potential, and electrical conductivity, were measured using calibrated probes, while soil organic matter content was determined through combustion at 450°C for 12 hours. Particle size distributions were established using the pipette method following pretreatment procedures (carbonate dissolution and organic matter removal). Total concentrations of major elements (Ca, Mg, Na, K) and trace metals (As, Co, Cr, Cd, Ni, Pb, Zn) were quantified by inductively coupled plasma optical emission spectrometry (ICP-OES) after aqua regia digestion. Quality assurance was ensured by employing NIST Certified Reference Material 2711a (Montana II soil), with recovery rates ranging from 90% to 108%.
Mineralogical compositions were characterized using X-ray diffraction (XRD), while soil microstructure and physical processes were investigated using scanning electron microscopy (SEM). Major oxide concentrations (SiO₂, TiO₂, Al₂O₃, Fe₂O₃, SrO, SO₃) were determined via X-ray fluorescence (XRF). This dataset provides valuable insights into the biogeochemical processes influencing soil formation, trace metal mobility, and environmental interactions in tropical island ecosystems
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“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
Get PDFWe 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
Hydrogeochemistry of shallow aquifer Manukan Island, Sabah
Get PDFA total of 180 shallow groundwater samples in Manukan island’s aquifer were collected for major and trace elements analysis in order to obtain a general understanding of the hydrogeochemistry in the study area. Groundwater and soil samples were collected in the low elevation area of the island to evaluate the general chemical composition of groundwater and soil, hydrogeochemical facies in the natural shallow aquifer as well as the mineralogy of the soil in the aquifer. A total of 10 boreholes were installed perpendicularly from the shoreline towards inland of the island. Different layer (O, A, E, B and C zone) of soil samples were collected from the soil core during coring process. For water samples analysis, in situ readings were recorded in the field. Chemical parameters such as chloride (Cl-), bicarbonate (HCO3-), calcium (Ca2+), magnesium (Mg2+), sodium (Na+) and potassium (K+) were analysed in the laboratory. For mineralogy analysis, soil samples were pulverized and sieved prior to X-ray diffraction (XRD) and X-ray Florescence (XRF) analysis. Visual verification of these minerals were obtained from the images captured by scanning electron microscopy (SEM). Measurements of the soil’s loss on ignition (L.O.I.) and total metals in the soil samples were also included in the results, respectively. The results indicate that the groundwater collected from the boreholes were moderately mineralized with EC ranged from 460 μS/cm to 3400 μS/cm. The previous indiscriminate pumping activities had led to seawater intrusion into the aquifer. This study shows that the groundwater were generally classified as Ca-HCO3, CaCl2, NaHCO3 and NaCl water type as illustrated in the Piper diagrams. This study also found that the PHREEQC calculations were in agreement with the soil geochemical composition data. The PHREEQC calculations for calcite, aragonite and dolomite solubility revealed positive values in the saturation indices (SI), indicating supersaturated state i.e. precipitation shall occur with respect to these minerals. The baseline geochemical results clearly revealed that the major chemical composition of the soil in the study area was mainly composed of quartz, calcite, aragonite as well as magnesium calcite. XRF analysis depicts a general trend where the soil chemical composition varies significantly with depth and distance from shore. The composition of calcium oxides increases with depth. Conversely, silicon oxide showed a decreasing trend in composition with increasing depth which dominated by carbonates minerals. SEM images visually showed the presence of quartz, calcite and aragonite minerals in the soil samples and further supports the data obtained from XRD
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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