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    Heavy Metals and Physico-Chemical Properties Inter-Relations in Agricultural Soils, Tanjaro Sub-District, Iraq

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    In the current study, agricultural soil samples were collected from 30 different locations in Tanjaro sub-district, north of Iraq. Soil samples were analyzed for identifying the concentration of 16 heavy metals and 9 soil property parameters using inductively coupled plasma optical emission spectroscopy (ICP-OES) and other analyzing tools. Multivariate and geospatial statistics have been applied to investigate links between heavy metals and soil properties. Descriptive statistics showed considerable variation exists in concentrations of the investigated parameters among sampling locations. Multiple correspondence analysis (MCA) revealed that the highest relationships were for soil organic matter (SOM), particularly with Cd, Co, and Hg. Agglomerative hierarchical clustering (AHC) and factorial analysis (FA) classified soil property relationships with heavy metals into three distinctive categories of heavy metals: naturally existed; originated from anthropogenic sources; and with no significant relationships. Plotting spatial variation of investigated soil parameters using Kriging interpolation for extracted factor from FA showed that soil properties in northern parts of the study area are more impacted by heavy metals came from anthropogenic activities. This study gives further insight into relationship patterns of soil properties with heavy metals, leading to improve the sustainability of agricultural land

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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

    Assessment of Heavy Metals Contamination in Drinking Water of Garmian Region, Iraq

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    Drinking water of safe quality is a critical issue for human survival and health. Water pollution by heavy metals is very crucial because of their toxicity. This study assesses potential of heavy metals pollution in drinking water in Garmian Region, East Iraq. Water samples were investigated for 23 heavy metals and 6 chemical contaminants collected from 16 locations. The analysis was performed by using coupled plasma optical emission spectroscopy (ICPOES, Spectro Arcos). High levels of Al, Se, Sr, and Fe have been detected at certain locations in study area. Statistical analysis techniques of the correlation matrix (CM), and cluster hierarchical analysis (CA) were conducted. The heavy metals pollution index (HPI), heavy metals evaluation index (HEI), and contamination Index (Cd) were used applied. These indices linked with the statistical analysis to interpret relationships among the tested parameters in water samples and to investigate the pollution sources over the study region. Even with the significant correlations between the HPI, Cd, and HEI, they showed dissimilar impact of examined heavy metals on the water quality. The most reliable pollution evaluation index of HEI for drinking water showed that 44% of the water samples is critically polluted. Sources of the contamination are most likely coming from natural geological sources. Anthropogenic impact was only noticed at several sites in the study area

    Dispelling the Myths Behind First-author Citation Counts

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    We 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

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We 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
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