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Abstract  

An accurate knowledge of the ratio Ca/P in bone biopsies is very useful in the diagnosis of osteoporosis. Similarly, measurements on muscle biopsies are important in understanding the disturbance of intracellular fluid and electrolyte (Na, Cl, K and P) balance in patients with metabolic myopathies (muscle diseases) and acid-base disturbances including renal failure. The ratio Ca/P in normal subjects was found to be 2.30. Similarly, the ratio K/P was found to be very nearly constant in normal subjects.

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pv. syringae and P. fluorescence caused disturbances of energy flow in PSII by lowering its efficiency ( Table 1 ). In comparison with absolute control values of parameters F v / F m and phenomenological fluxes (energy absorption ABS, energy

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Abstract  

In machine drawn weldor safety glasses with a different protection grade and a total iron oxide content of 6.8–9.5% the lattice coordination of iron and the Fe2+/Fetot ratio were determined by Mössbauer spectroscopy. In combination with electron beam microanalysis and specific sample preparation, homogeneity disturbances were observed inside the defect glass as well as on its surface.

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Community Ecology
Authors: B. Tajthi, R. Horváth, Sz. Mizser, D. D. Nagy, and B. Tóthmérész

Urban areas have been growing radically worldwide, causing considerable changes in biodiversity of natural habitats. In floodplain forests, we studied the effects of urbanization on ground-dwelling spider assemblages along a rural–suburban–urban gradient in Hungary. We tested three traditional hypotheses (intermediate disturbance hypothesis, habitat specialist hypothesis and hygrophilous species hypothesis) and two novel expectations (shade-preferring species hypothesis, and disturbance sensitive species hypothesis) on spiders. We found that the total number of species was higher in the suburban habitat than in rural and urban ones, supporting the intermediate disturbance hypothesis. We found a decrease in the species richness of forest specialist and shade-preferring species along the urbanization gradient. We found that the number of hygrophilous and disturbance sensitive species was the lowest in the urban habitat. The spider assemblages of the rural and suburban habitats were clearly separated from the assemblages of urban habitats. Based on our findings we emphasize that low and moderate intensity of forest management contributes to the preservation of the local species richness in floodplain forests.

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Abstract  

In the course of ion-exchange separations of highly active solutions, the radiolysis gives rise to considerable disturbances and deteriorated separation results. On the example of241Am/242Cm separations some results of radiolysis investigations for Dowex 50X8 are briefly shown, and experiences with the choice of parameters of a high-pressure column system are described for several examples.

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A new closed rock sward association ( Festuco rupicolae-Arrhenatheretum Erdős et Morschhauser, ass. nova.) has been found and described in the Villány Mts (SW Hungary). This community lives in northern expositions, near the ridge or the plateau. Bedrock is limestone and dolomite. In the association dominated by the grasses Festuca rupicola and Arrhenatherum elatius , an unusual mixing of species can be encountered: species of the mesophilous forests, of the karst shrub-forests and of the xerophilous grasslands and rock swards occur together in this community. Description of the new community as a distinct association is supported by the PCoA ordination and the differential species. Ecological properties of the community were characterised by using ecological indicator values. This analysis also shows the dual character of the association. We analysed the new association by computing the spectra of the social behaviour types. The extraordinarily great amount of the disturbance tolerants is probably a consequence of the former grazing pressure or some other disturbance.

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Modern biodiversity research focuses on multiple diversity facets because different indices may describe different ecological and environmental processes, as well as the effects of varied disturbances of natural and anthropogenic origins. We investigated littoral macroinvertebrate diversity in a large boreal lake system and specifically explored congruence of indices within and between the three diversity facets: species diversity, functional diversity and taxonomic distinctness. First, we found that the indices of taxonomic distinctness were the most sensitive indicators of eutrophication. Second, we observed that most correlations between the indices within the same diversity facet, and between the indices of functional and species diversity, were relatively strong. However, the indices of taxonomic distinctness (Δ+ and Λ+) were weakly associated with other metrics of diversity, emphasising the importance of taxonomic distinctness as a complementary dimension of biodiversity. Therefore, our observations support the importance to examine multiple facets for mapping biodiversity or for assessing the effects of anthropogenic disturbances on biological communities.

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The stability behaviour of a thin-film superconductor under a localized release of thermal disturbance is investigated. Two-dimensional conjugate film/substrate conduction equation with anisotropic thermal conductivity of the film, and Joule heat are employed to investigate effects of substrate and thermal properties on the intrinsic stability and quenching recovery. To consider the thermal boundary resistance between film and substrate, an interfacial-layer model (ILM) with very low diffusivity and an acoustic mismatch model (AMM) are employed. Results show that the thermal boundary resistance influences strongly the intrinsic stability. Thermal boundary resistance increases intrinsic stability if the thermal conductivity of the substrate or the disturbance energy is large. Higher Biot numbers and thermal conductivity ratios of film to substrate in longitudinal direction influence stability favorably. We demonstrate also that operation of a film/substrate system, such as YBCO/MgO, is either intrinsically stable or irrecoverably unstable.

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Abstract  

The mass spectrum of secondary ions emitted from a solid surface under ion bombardment is characteristic of the composition of the superficial monolayers. By the use of very low primary ion current densities and highly sensitive detection techniques, analysis can be performed without measurable disturbance of the original first monolayers. Some results demonstrating the capabilities of this ‘static’ method of secondary ion mass spectrometry (SIMS) are presented.

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Mediterranean forests are especially prone to fire, a periodic disturbance that affects all the ecosystem components in different ways. Gathering knowledge on the particular responses and rate of recovery of multiple ecosystem components following a wildfire is crucial to reliably evaluate its consequences on biodiversity. Using eight sampling transects, we studied the changes in four ecosystem components (topsoil, plants, carabids, and staphylinids) during three years after a spring wildfire in a Quercus pyrenaica forest; and compared them with the surrounding unburnt forest (hereafter control). We found great variety of responses to fire suggesting each component may deal with this recurring disturbance via different adaptations, and that the time spent to recover to pre-disturbance conditions depends on the group of focus. Topsoil characteristics were highly variable and minor differences were found between burnt and control transects. Plant community was considerably affected by fire but rapidly recovered exceeding the control forest in species richness and cover, partly due to proliferation of annual herbs. However, plant species composition differed between burnt and control forests during the whole study period. Carabid beetles were more abundant and richer in species in the burnt forest, thanks to the arrival of seed predators favoured by post-fire drier and warmer conditions. Staphylinid beetle composition differed between control and burnt transects during the whole period, although their abundance was strongly variable. Distinct post-fire plant, carabid and staphylinid species composition suggests scattered low-intensity wildfires in this region may help to maintain habitat heterogeneity benefiting biodiversity at the landscape scale.

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