1,720,991 research outputs found
The ore forming potential of calc alkaline systems: a magmatic perspective
No full textThe association of porphyry copper style mineralisation with extensive calc alkaline igneous activity is not in doubt. However, the role of the magmatic system in the formation of such deposits is still not fully understood. Extensive works have investigated the associated alterations, ore petrology, fluid compositions and the theoretical models of ore metal transference from magma to hydrothermal fluid. Despite these numerous studies, little or no information on the chemical composition and physical processes that occur in the magmatic system has been forthcoming. Silicate melt inclusions provide a method of directly sampling the volatile and ore metal content of magmatic systems. A study of a copperrich andesite from Hahajima, Japan, demonstrates that though the majority of calc alkaline systems have the potential to form a porphyry copper deposit, the physiochemical conditions of the magma chamber prevent most from doing so. The melt inclusions contain significant amounts of copper (up to 2000ppm), which exceed the average andesitic melt copper content by several orders of magnitude. Measured average water content of 3.3 wt%, and a CI/H2O ratio of 0.06 from the melt inclusions are typical of those expected for an arc andesite. The analysis of samples from the Morenci and Chino porphyry copper deposits of the SW USA showed that the melt inclusions contained a maximum of c.700 ppm Cu. By employing a fractional crystallisation model it is possible to demonstrate that melt responsible for the formation of these deposits was not an exotic copper-rich melt. However, both of these deposits displayed trace element characteristics similar to those of Adakites. A study of copper-rich quartz-included biotites from Morenci demonstrated that the parental magma of this system had a small but significant amount of crustal contamination. The copper enrichment in these biotites is the consequence of the mineral's interaction with a copper-carrying exsolved magmatic volatile phase which was in equilibrium with the melt. The quartz phenocrysts from Morenci, which host the melt inclusions and biotites have a complex history of growth and resorption. These events are faithfully recorded by the quartz's zoning. It is possible by the application of existing crystallisation models to demonstrate that during the later stages of the Morenci magma's crystallisation that a magmatic volatile phase was undergoing cycles of undersaturation, saturation and exsolution. This 'pumping' of volatiles was driven by the phenomenon of undercooling. These studies of calc-alkaline magmatic systems and their contribution to the porphyry copper-forming process, serve to provide some ground truths to the current models used to understand their formation and may provide the basis for the development of future exploration tools
Socioeconomic position and mass media campaigns to prevent chronic disease
No full textThis cross-sectional study of a 45 to 60 year old Brisbane population examined socioeconomic differences in campaign reach, understanding of health language, and effectiveness, of a recent mass media health promotion campaign. Lower socioeconomic groups were reached significantly less and understood significantly less of the health language than higher socioeconomic groups thus contributing to the widening of the health inequality gap
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
Anger and anxiety in patients with primary aldosteronism treated with amiloride hydrochloride or spironolactone or adrenalectomy
No full textIn Primary Aldosteronism (PAL) excessive amounts of aldosterone cause sodium and water retention and, in many individuals, this leads to moderate to severely high blood pressure. Although the chemistry and physiology are increasingly well understood, including the outcomes of treatment on physical health, there has been no systematic study of the psychological dimension of PAL. Anecdotally, patients exhibit symptoms such as angry outbursts, irritability, anxiety and defensiveness, and partners of these patients sometimes mention poor anger control and brittle or unpredictable moods. This thesis reports a systematic study of anger and anxiety among patients undergoing treatment for PAL. Eighty-three patients were recruited over an 11-month period to a prospective, pre-post design study to determine if treatment was associated with change in psychological state. Participants completed the State-Trait Anger Expression Inventory (STAXI-2), State-Trait Anxiety Inventory (STAI) and Psychosocial Adjustment to Illness Scale (PAIS) questionnaires. Adrenal Vein Sampling confirmed overproduction of aldosterone in one or both adrenal glands. Patients with Aldosterone Producing Adenoma (APA) were offered adrenalectomy. As per usual treatment protocols, patients with Bilateral Adrenal Hyperplasia (BAH) were prescribed spironolactone or amiloride depending predominantly on severity of blood pressure and potassium levels. Post-test questionnaires were completed after 6-8 months. Analysis was by mixed design (between-within subjects) ANOVA. Participant numbers in the adrenalectomy group fell far short of expectations. Fourteen past patients who had undergone unilateral adrenalectomy completed a retrospective semi-structured questionnaire. This qualitative data was analysed to identify themes similar to quantitative data. At baseline, 'non-completers' (ie those who did not complete the post-test; n=19), were significantly more angry than 'completers' (n=50) in State Anger (p< .01), Trait Anger (p< .05) and Anger Expression Index (p< .001). Trait Anxiety was also higher (p< .05), as was Psychological Distress (p< .05). Among those who participated at both interviews, there was small but statistically significant adverse treatment effect with higher scores for State Anger (p< .05), and Feeling Angry (p< .05). However for Trait Anger (p< .01), and 2 of its 3 sub-scales Angry Temperament (p< .05) and Angry Reaction (p< .01) there was a slight to moderate decrease in negative affect with treatment. Psychological Distress scores also improved (p< .05). Across all ANOVAs, there were no significant interaction effects, suggesting that any treatment effect was equivalent for the two drugs. Qualitatively collected data elucidated participants' changes in approach to life and relationships since adrenalectomy. Themes that emerged in the data included improved ability to cope with external stress, better control of emotions, more relaxed relationships and attitude to work, and a greater vitality and quality of life. Generally the comments were consistent with the drug treatments; there was noticeable benefit, including perceived better anger control and less anxiety. Positive psychological effects of treatment observed in the two drug groups were triangulated with data from a qualitative study. The combined evidence suggests that when excess circulating aldosterone is reduced (adrenalectomy), or blocked (spironolactone), or aldosterone's salt and water retaining effects are minimised (amiloride), then nervous irritability and its subsequent psycho-behavioural manifestations are reduced. The effect however is slight and the conclusions are weakened by an apparent attrition bias, and the absence of a control group. Implications for further research are discussed
The Geographical Patterns of Socio-Economic Well-Being of First Nations Communities in Canada
Full text linkCommunity/Rural/Urban Development, Labor and Human Capital,
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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