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Due to its nonlinearity with respect to species addition, some applications of the Rao quadratic diversity are meaningful only if they are first transformed into their equivalent number of species, which is the theoretical species richness of a maximally distinct and perfectly even community with the same diversity as the original community. In this paper, relaxing the requirement of maximal distinction among species, we generalize the notion of the equivalent number of species for the Rao diversity to partially distinct species. The biological meaning of this proposal is illustrated with one dedicated case study in sand dune communities in Italy. According to our results, the proposed approach proved appropriate for comparing the functional diversity of different plant communities with varying levels of environmental constraints.

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Structure and diversity trends (β-diversity and species richness) across the Fagus sylvatica timberline in the central Apennines were investigated. Twenty-three belt transects were laid out across the upper forest line in the Simbruini Mountains. Number of species, plant cover, and height of different layers were recorded in each quadrat. The moving split-window method was used to detect ecological discontinuities across beech timberlines. We show how β-diversity changes along timberlines and we put forward some hypotheses about the possible dynamics of these transitions. Fourmodels resulted from the analysis of β-diversity trends: two β-diversity peaks indicated a transition where shrubs, mainly Juniperus communis ssp. alpina, (two high peaks) or beech scrub (two small peaks) formed a mantle that could allow forest expansion. One high β-diversity peak referred to an anthropo-zoogenic boundary maintained by disturbance, without the presence of a mantle. A little peak indicated a gradual transition at the upper potential timberline limit where beech forest had lost its typical floristical composition and structural characteristics.

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This study is part of a general project to analyse the biological and ecological mechanisms that influence the invasion of Mediterranean sand dune ecosystems by alien plants. In this paper we analyse the morphological and functional traits of coastal dune wild species (natives and aliens) based mainly on information from the literature. The most common 130 wild species occurring on the recent (Holocenic) coastal dunes were included considering the invasive status of alien plants. A comparative analysis of functional groups was performed through ordination techniques (PCoA using the Gower index). This reveals four functional groups related to the most important plant communities in coastal vegetation zonation. Alien plants were found in all functional groups and no trait or set of traits was specifically related to them. This indicates that aliens show similar traits to those natives growing in different communities of the coastal dune zonation, from the small beach annuals to the evergreen taller shrubs of the Mediterranean macchia. When the invasive status of alien species was taken into account, however, some differences emerged: a) casual aliens were found in almost all groups but their traits were not interpreted as being due to any particular adaptive strategy; b) naturalised aliens were only found in the less fluctuating habitats of the inner coastal zones; c) invasive alien species were connected with two major plant strategies: annual invasive aliens (quick-to-mature low grasses and herbs) and perennial invasive aliens (taller and often strongly clonal).

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Abstract  

An effective modification of the chemical processes has been obtained to dissolve uranium(IV) and extract it as uranium triperoxocomplex, which facilitates its manipulation and final conversion into uranium nitrate as a high purity concentrate.

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We investigate the modifications of soil factors in Carpobrotus invaded sites by evaluating differences between non-invaded and highly invaded plots in three habitats of coastal dune ecosystems in Central Italy. Nitrogen content, organic matter content, pH and salinity were measured in three coastal habitats: shifting dunes along the shoreline with Ammophila arenaria, Crucianellion maritimae fixed beach dunes and fixed coastal dunes with Juniperus spp. Soil variables of the invaded plots were compared to non-invaded ones using two-way factorial ANOVAs and post-hoc Tukey HSD tests. We found significant differences between invaded and non-invaded plots for nitrogen content, organic matter content and pH in both foredune habitats. On the other hand, no differences were revealed on fixed dunes. Thus, we found distinct responses of soil factors to Carpobrotus invasion depending on the habitat. Pioneer habitats with very poor soils are more sensitive to invasion probably because the production of litter by Carpobrotus is considerably higher than for native species. Therefore, for the establishment of efficient alien control programs of those habitats of conservation interest, it is imperative to take into account the relationship between invasive species presence and the top soil characteristics. For instance, particular attention is required in the foredune zone (pioneer habitats), where Carpobrotus invasion is more likely to affect the parameters of the soil.

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Abstract  

The Na4UO2(O2)3·8H2O complex was prepared from aqueous systems and its crystallographic and chemical structural conformation characterized. IR spectroscopy and X-ray diffraction were used for analyzing the solid crystal extracted with ethanol to determine the anionic compositon. Composition of the solid phase did not depend on the molar ratio of the reactants or on the pH of the medium, but only upon the absolute concentrations of uranium and alkali. It was observed that the temperature significantly influenced the crystal structure of the product and that a limit to the UO2 concentration existed for inducing the production of a mixture of soluble and insoluble species.

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Abstract  

IGCC slag is a vitreous residual product from the new induction gasification combined cycle gasification thermal power plants. In order to characterize this waste as secondary new material for the production of new glasses and glass-ceramics as construction materials; this slag from the Puertollano, Ciudad Real, Spain power plants has been fully thermally investigated. After controlled heating this waste gives rise to hematite, anorthite, and cristobalite crystallized materials.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Perera Pintado
,
S. Mather
,
M. Stalteri
,
D. Allison
,
A. Prats Capote
,
A. Hernández Cairo
,
O. Reyes Acosta
, and
M. Bequet Romero

Abstract  

The aim of this work was to characterize the in vitro behavior of N4- and N3S-RGDS-derivative peptides labeled with 99mTc. Peptides AGGG-Abu-GRGDSPK-NH2 (F22) and C(acm)-GGG-Abu-GRGDSPK-NH2 (SMA1) were synthesized by solid phase. The stability of 99mTc-labeled peptides was assessed in a 30-fold molar excess of cysteine and in plasma. The affinity for plasma proteins was also evaluated. Labeling yield was >95% for both peptides. 99mTc-F22 was not stable in presence of cysteine, but 63% of 99mTc remained chelated to SMA1 up to 24 hours. Both peptides showed low affinity to plasma proteins. N3S-RGDS-derivative peptide (SMA1) showed more stable coordination binding with 99mTc and a higher stability in plasma with regard to N4-RGDS-derivative peptide (F22).

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