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The Hero's Journey is a universal pattern. Although it can be infinitely varied, the basic form is both universal and constant. Kossuth first crossed the threshold when he entered national politics. After his imprisonment for disloyalty and sedition, he emerged as a national martyr and hero. He became and remained a revolutionary. He never reached the resurrection stage, made no compromise, and became a symbol for independence and liberty.

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Testing the ecological communities of different areas for convergence, in the sense of remarkable similarity in the characteristics of the species present, has a long history in biology. Recently, numerical methods have been developed for comparing community-level convergence to an explicit null model. No valid method has been known for testing the significance of texture convergence when the species are weighted by their abundance. Six combinations of method variants are tested on random datasets. A valid P value (i. e., with P . 0. 05 in no more than 5% of the cases) is obtained so long as for each species the distribution of abundances across sites is retained, and only the assignment of character values is randomised. Further restriction is not necessary for obtaining a valid P value, and can lead to a test with considerably lower power to detect convergence. The power of the test with free matching of character values to species is only moderate with 10 sites, though improved with larger numbers of sites. Previous methods for detecting texture convergence have examined convergence only in the mean value for any character. It is possible that the external environment might be reflected in the community mean of a character, leaving the imprint of convergence on the shape of the distribution, rather than the mean. A method for comparing the shape is described, and it is shown that the null model is valid also for this test statistic.  

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Assembly rules are measures of community structure that link observed patterns with ecological processes, and as such may help to elucidate the mechanisms by which species coexist. We apply two approaches to a lawn community - limiting similarity and guild proportionality - hoping that agreement between them might give robust conclusions. We tested for agreement between these two assembly rules using functional characters that are related to two aspects of species function - light capture and response to defoliation. We combined point quadrat data and a null model approach to test for limiting similarity - a tendency for species differing in functional characters to co-occur more often than expected at random - in turves extracted from the lawn community. Examining the variance in the characters of the species co-occuring at each point, evidence for limiting similarity was found for mowing removal (the proportion of leaf area removed in mowing events). There was greater variation between the species co-occurring at a point than expected at random (i.e., under an appropriate null model). However, no such evidence was found for characters related uniquely to light capture, such as specific leaf area and pigment concentrations. In a previous study in the same community, “intrinsic” guilds had been determined from co-occurrences within the lawn community and from a competition experiment, as those effective in determining species assembly and co-existence. These intrinsic guilds are shown by t-test to differ in the proportion of their biomass removed in mowing (MRI), which is of course related to the height at which their leaf area is held. However, again no differences were seen in characters related uniquely to light capture. Thus, the two different approaches to assembly rules - guild proportionality and limiting similarity - agree that differences in response to mowing are responsible for species co-existence in the lawn community. The agreement between these two approaches, tested on independent datasets of quite different type from the same community, gives possibly the strongest evidence so far that niche differentiation may be responsible for local co-existence in plant communities. However, although MRI is related to this co-existence the lack of correlation with light-capture characters leads to speculation that the effects might be via the below-ground behaviour of the species.

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Abstract  

The applications of a conventional 2.5 MeV Van de Graaff machine for analytical work using a beam of accelerated protons or deuterons is described. These applications include (1) the depth concentration of deuterium in steels using a nuclear reaction technique, (2) the location of3He atoms in the erbium hydride lattice using ion channelling and (3) the identification of vanadium oxides formed by sputtering using Rutherford backscattering and electron diffraction. Provisional results are presented.

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The objective of this research was to design an extraction media and procedure that would selectively remove uranium without adversely affecting the soils' physicochemical characteristics or generating secondary waste forms difficult to manage or dispose of. Investigations centered around determining the best lixiviant and how the various factors such as pH, time, and temperature influenced extraction efficiency. Other factors investigated included the influence of attrition scrubbing, the effect of oxidants and reductants, and the recycling of lixiviants. Experimental data obtained at the bench-and pilot-scale levels indicated 80% to 95% of the uranium could be removed from the uranium-contaminated soils by using a carbonate lixiviant. The best treatment was three successive extractions with 0.25M carbonate-bicarbonate (in presence of KMnO4 as an oxidant) at 40°C followed with two water rinses.

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Neutron activation analysis was used to investigate and quantify the level of heavy metal uptake in the marine environment of Lake Austin in Austin, TX. Specifically, the samples studied were largemouth bass, or micropterus salmoides. The presence of heavy metals in the food chain presents multiple hazards, mostly as a food hazard for those species that ingest the fish, namely humans. To measure the concentrations of heavy metals in various fish samples, the nuclear analytical technique of neutron activation analysis (NAA) was used. Both epithermal and thermal irradiations were conducted for the NAA to look for short and long-lived radioisotopes, respectively. The samples themselves consisted of liver and tissue samples for each of the fish caught. Each sample was freeze-dried and homogenized before irradiation and spectrum acquisition. The results showed that all levels of heavy metals were not sufficient enough to make the fish unsafe for eating, with the highest levels being found for iron and zinc. Gold was found to be at much higher concentrations in the younger fish and virtually non-existent in the larger of the samples.

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Both local and regional factors determine local species richness. We investigated the relative role of local (13 soil and tree stand structure variables) and regional factors (19 climate, land cover and geographic location variables) in determining the richness of several vascular plant functional groups in indigenous forest fragments in southeastern New Zealand. The predictor variables explaining the largest fraction of the variation in species richness were identified using a backward and forward stepwise procedure, with adjustments for the number of variables and testing for multicollinearity. The total proportion of variation explained by local and regional factors was highest for tree species richness (54.1%) and lowest for herbaceous species richness (28.2%). We found differences between the functional groups in the extent to which species richness was explained by local vs. regional factors, but both showed some ability to explain the species richness of all functional groups. The abundance of the strongly competitive tree species Nothofagus menziesii (silver beech) had a strong negative effect on total, tree and herb species richness, but it had only minor effects on woody and fern species richness. Once the effect of this local variable was accounted for, the remaining variation in tree and woody species richness was mainly explained by regional variables. Herbaceous and fern species richness, on the other hand, was strongly correlated with local as well as regional variables. We emphasize the importance of using a fixed plot size when the relative effects of local and regional factors on patterns of species richness are to be compared and evaluated.

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Abstract  

Interdisciplinary synthesis and validity analysis (ISVA), a structured learning approach which integrates learning and communication theories, meta-analytic evaluation methods, and literature management-related technologies was applied in the context of the 1993–1997 bovine mastitis research literature. This study investigated whether ISVA could: 1) facilitate the analysis and synthesis of interdisciplinary knowledge claims, and 2) generate projects or research questions. The bovine mastitis-related literature was conceptualized as composed of microbiological, immunological, and epidemiological dimensions. Keywords involving these dimensions were searched in theMedline andAgricola databases. A final list of 148 articles were retrieved, analyzed, synthesized into fifteen information sub-sets, and evaluated for construct, internal, external and statistical validity through an interdisciplinary iterative dialogical process. Validity threats were re-phrased as new research or educational projects.

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