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Abstract  

Eight out of the fourteen rare earth elements were estimated from the leaves ofPelthophorum pterocarpum, the leaves and roots ofImpatiens balsamina, and the soils from four sampling sites by instrumental neutron activation analysis. The chondrite normalized rare earth element abundances and distribution patterns in the plant materials were found to be significantly correlated to the abundances of the rare earth elements occurring in the soils. The extent of accumulation of the rare earth elements in some plant materials was also govemed by the age of the plants and the plant organs.

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Abstract  

A systematic investigation using a variety of handguns has revealed the existence of distinguishable distribution patterns of firearm discharge residues on surfaces below the flight path of a bullet. The residues are identifiable even at distances of 12 meters from the gun using nondestructive neutron activation analysis. The results of these investigations show that the distribution pattern for a gun is reproducible using similar ammunition and that there exist two distinct regions to the patterns developed between the firearm and the target—one with respect to the position of the gun and the other in the vicinity of the target. The judicious applications of these findings could be of significant value in criminal investigations.

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Abstract  

The distribution patterns of Classic Mimbres black-on-white bowls and jars were determined by instrumental neutron activation analysis to identify vessel movement between geographically defined regions and between villages within individual regions of southwestern New Mexico. The data set produced and utilized by the various multivariate statistical treatments included multielement neutron activation analysis results for 288 ceramic and clay samples from 15 sites in the Gila, Mimbres and Rio Grande valleys of southwest New Mexico. The results indicate that bowls were more frequently exchanged than jars and distribution frequencies between regions were lower than between villages. Two statistical approaches to the data were compared. In one, cluster analysis of the compositional data was used to form homogeneous groups and the distribution of those groups across sites and regions was examined. In the second, discriminant analysis was used to look for significant differences in composition between regions and sites. The significance of predetermining groups based on collection location as opposed to blind group formation from hierarchical cluster analysis was evaluated in terms of its potential to lead to different interpretations of the data.

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Abstract  

Trace element determinations at 60 samples of Deep Sea Drilling Project Leg 37 from the Mid Atlantic Ridge south of the Azores had been accomplished by instrumental neutron activation analysis. The elements Na, Mn, Fe, Sc, Cr, Co, Rb, Sb, Cs, La, Ce, Nd, Eu, Tb, Dy, Yb, Lu and Hf were determined with satisfying accuracy. The chondritenormalized rare earth distribution patterns showed strong variations within one drill hole. The different REE patterns require a new interpretation for the generation of this part of the oceanic crust. New considerations for the mode of formation of the oceanic basaltic crust are presented.

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Abstract  

Molecular activation analysis based on biological separation techniques combined with instrumental neutron activation analysis (INAA) was applied to study the distribution patterns of 24 elements, including essential and unknown trace elements in the liver organelles. Concentrations of As, Au, Co, I, Mg, Mo, Sb, Sc, Se and Th were found to be the highest in nuclei and mitochondria, while those of Br, Cl, Cs, Cu, K, Na, Rb and V were found to be in cytosol. Concentrations of Al, As, Au, Ba, Fe, I, Sb were found to be the lowest in cytosol. The element As was mainly present in the nuclear fraction, where its concentration was two to four times higher than that in other fractions. Ca and Fe were highly enriched in the microsomal fraction.

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Abstract  

Results obtained from the analysis of sediments surface samples taken from rivers mouth and polluted marine environment were analyzed for REE contents to determine the concentrations of La, Ce, Sm, Eu, Tb, Dy, Lu and Yb using instrumental neutron activation analysis. Thirty surface samples were collected from ten sites in the coastal marine sediments of the South China Sea along 957 km stretch of the east coast of Peninsular Malaysia. The samples prepared in the powdered form before irradiating them in a neutron flux of ~4 × 1012 n cm−2 s−1 at 750 kW power using the TRIGA Mark II research reactor at Malaysian Institute for Nuclear Technology (MINT). Results of the total concentration are used to establish baseline data in environmental pollution assessment and to develop the correlations between the Ce/Ce* anomalies and the distribution patterns of some the light rare earth elements (LREEs) and the heavy rare earth elements (HREEs). The Chondrite-normalized REE pattern from each site examined and used to explain the sedimentation patterns by anthropogenic activities and by natural processes such as shoreline erosion, weathering deposits. Shale-normalized (NASC) patterns suggest enrichment of LREEs relative to the HREEs with a positive Ce/Ce* anomaly. Validation of the used method was done using a Soil-7 SRM.

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. Riverside, pp. 1-135. Sáchez, J. A., Lacasa, A., Gutiérrez, L. and Contreras, J. (1997): Distribution pattern and binomial sampling for Frankliniella occidentalis Orius spp. in sweet pepper crops. Bulletin OILB

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Abstract  

The abundance and distribution of rare earth elements (REE) and their signatures in the Wuding River of China were studied from samples of surface sediments and related to the geological formation in its watershed. The total REE (ΣREE) average concentrations of the Wuding River sediments (144.56 μg g−1), is lower than that in the Yangtze River sediments (167.10 μg g−1), getting closer to the values of the Yellow River sediments (137.76 μg g−1), being equivalent to the values of the UCC (the upper continental crust) (146.37 μg g−1). The chondrite-normalized REEs indicated LREE enrichment and flat HREE depletion and also showed a slightly negative Eu-anomaly. A similar chondrite-normalized REE distribution pattern between the Wuding River sediments and Yellow River sediments demonstrated the Wuding River sediments are the important material sources of the Yellow River sediments. UCC-normalized REE patterns between the Wuding River sediments and the Yellow River sediments were almost equivalent and close to the UCC. These implied the Wuding River sediments and the Yellow River sediments are subjected mostly to physical weathering due to higher erosion rates. Consequently, they can be used to trace the UCC compositions.

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Abstract  

In this study an attempt to examine the dependence between the productivity of core journals and the shape of the distribution curve in the upper section is made. For this purpose, the impact of the core journal productivity increase over an extended time interval was investigated. As a referent point in relation to which the changes were followed, equalized inverse relationship between the core and periphery in terms of the number of journals and the number of papers published in them in a given subject field has been hypothesized. The degree to which a particular set of data conforms to that relationship expressed as , is taken as an indicator of the changes in the core/periphery relation. The applicability of Lotka's exponent in the journal productivity context is also discussed.

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Community Ecology
Authors: S. Ongaro, S. Martellos, G. Bacaro, A. De Agostini, A. Cogoni, and P. Cortis

The Mediterranean is one of the major biodiversity hotspots of the world. It has been identified as the “core” of the speciation process for many groups of organisms. It hosts an impressive number of species, many of which are classified as endangered taxa. Climate change in such a diverse context could heavily influence community composition, reducing ecosystems resistance and resilience. This study aims at depicting the distribution of nine orchid species in the island of Sardinia (Italy), and at forecasting their future distribution in consequence of climate change. The models were produced by following an “ensemble” approach. We analysed present and future (2070) niche for the nine species, using Land Use and Soil Type, as well as 8 bioclimatic variables as predictors, selected because of their influence on the fitness of these orchids. Climate change in the next years, at Mediterranean latitudes, is predicted to results mainly in an increase of temperature and a decrease of precipitation. In 2070, the general trend for almost all modelled taxa is the widening of the suitable areas. However, not always the newly gained areas have high probability of presence. A correct interpretation of environmental changes is needed for developing effective conservation strategies.

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