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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.
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.
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.
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.
Abstract
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.
Abstract
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.
Ecotones have long been a focus of ecological research, and there is considerable current interest in functional traits in community ecology. Yet, surprisingly, the functional trait approach has not been applied to ecotones. A bog-forest sequence in southern New Zealand was sampled with a grid of quadrats, and eight traits related to leaf function were measured on the 54 species found. Two ecotones were identified using moving-window analysis: Ecotone I was the transition from bog to edge forest, and Ecotone II was the transition from edge forest to tall climax forest. No strict ecotonal species were present. In contrast to theoretical predictions, species richness was not higher or lower in either ecotone, rather, both ecotones represented a transition in richness from one community to the other. It has long been said that ecotones are mosaics, but species mosaicity was no higher in either ecotone than in the adjacent communities, in fact it was lower in Ecotone I. Functional trait diversity decreased along the sequence from bog to forest, with no deviation in either ecotone. However, examining mosaicity in terms of traits, there was a steady rise in Ecotone I and, in conformance with ecotone / functional trait theory, a clear peak in Ecotone II. We conclude that the features claimed for ecotones are often not present, and whether they are present is dependent on the components measured: species vs traits. Here, the clearest patterns were seen in trait mosaicity, but even this differed markedly between the two ecotones. Generalisations about ecotones should be avoided; they will vary from ecotone to ecotone, and probably depend on the type of ecotone: anthropogenic, environmental, switch, etc.
To remain independent and healthy, an important factor to consider is the maintenance of skeletal muscle mass. Inactivity leads to measurable changes in muscle and bone, reduces exercise capacity, impairs the immune system, and decreases the sensitivity to insulin. Therefore, maintaining physical activity is of great importance for skeletal muscle health. One form of structured physical activity is resistance training. Generally speaking, one needs to lift weights at approximately 70% of their one repetition maximum (1RM) to have noticeable increases in muscle size and strength. Although numerous positive effects are observed from heavy resistance training, some at risk populations (e.g. elderly, rehabilitating patients, etc.) might be advised not to perform high-load resistance training and may be limited to performance of low-load resistance exercise. A technique which applies pressure cuffs to the limbs causing blood flow restriction (BFR) has been shown to attenuate atrophy and when combined with low intensity exercise has resulted in an increase in both muscle size and strength across different age groups. We have provided an evidence based model of progression from bed rest to higher load resistance training, based largely on BFR literature concentrating on more at risk populations, to highlight a possible path to recovery.
