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Rana Baydoun, Omar Samad, Maria Aoun, Bilal Nsouli and Ghassan Younes

Abstract

A new radiocarbon laboratory has been established recently at the Lebanese Atomic Energy Commission. This laboratory consists of benzene synthesis line and a low background liquid scintillation counter, Tri-Carb 3180 TR/SL for measurements with Bismuth Germanate (BGO) guard detector. The effectiveness of the benzene line was tested firstly by preparing benzene from a wood sample after carbide and acetylene receiving. Normalization and standardization of the liquid scintillation counter was carried out, as well as the Factor of Merit (E2/B) was determined for three different counting regions. To assure accuracy and reliability of results, reference materials were used. Based on z-score and u-score evaluation, as well as Student’s t-test, acceptable data were obtained from travertine and wood samples available through the International Atomic Energy Agency (IAEA-C2 and IAEA-C5), and humic acid (U) and murex shell (R) from the Fifth International Radiocarbon Intercomparison (VIRI). After that, a preliminary study was done, which is the base for future research in order to assess the anthropogenic impact and degree of environmental pollution in terms of radiocarbon isotope ratio (Δ14C) deduced from the Percent Modern Carbon or PMC. This work represents the results of four reference materials and those of five green grass samples. The Δ14C of green grass samples collected from two different clean zones were found to be 50‰ and 52‰, while the values of those collected from different polluted zones were 23‰, 7‰ and 15‰.

Open access

Rana Baydoun, Omar El Samad, Bilal Nsouli and Ghassan Younes

Internal method validation The purpose of the validation is to verify that the conventional radiocarbon method, used for the determination of radiocarbon content in tree leaves, grass and wood, when applied in our laboratory, fits to its intended use. Trueness Trueness was used to test the closeness of analytical result to the reference value and it was quantified in terms of bias ( Taverniers et al ., 2004 ). As well as, a statistical parameter, z -score was used to test the acceptance of the results. The whole working procedure consisting of benzene

Open access

Bálint Csendes and László Mucsi

Abstract

Hyperspectral remote sensing combined with advanced image processing techniques is an efficient tool for the identification of agricultural crops. In our study we pursued spectral analysis on a relatively small sample area using low number of training points to examine the potential of high resolution imagery. Spectral separability measurements were applied to reveal spectral overlapping between 4 crop species and for the discrimination we also used statistical comparisons such as plotting the PC values and calculating standard deviation of single band reflectance values on our classes. These statistical results were proven to be good indicators of spectral similarity and potential confusion of data samples. The classification of Spectral Angle Mapper (SAM) had an overall accuracy of 72% for the four species where the poorest results were obtained from the test points of garlic and sugar beet. Comparing the statistical analyses we concluded that spectral homogeneity does not necessarily have influence on the accuracy of mapping, whereas separability scores strongly correlate with classification results, implying also that preliminary statistical assessments can improve the efficiency of training site selection and provide useful information to specify some technical requirements of airborne hyperspectral surveys.

Open access

Piotr Androsiuk, Katarzyna Chwedorzewska, Kamil Szandar and Irena Giełwanowska

Abstract

Antarctic pearlwort (Colobanthus quitensis) is one of the flowering plant species considered native to maritime Antarctica. Although the species was intensively analyzed towards its morphological, anatomical and physiological adaptation to local environment, its genetic variability is still poorly studied. In the presented study, a recently developed retrotransposon-based DNA marker system (inter Primer Binding Site – iPBS) was applied to assess the genetic diversity and differentiation of C. quitensis populations from King George Island (South Shetland Islands, West Antarctic). A total of 143 scoreable bands were detected using 7 iPBS primers among 122 plant specimens representing 8 populations. 55 (38.5%) bands were found polymorphic, with an average of 14.3% polymorphic fragments per primer. Nine of all observed fragments were represented as a private bands deployed unevenly among populations. Low genetic diversity (on average He = 0.040 and I = 0.061) and moderate population differentiation (FST = 0.164) characterize the analyzed material. Clustering based on PCoA revealed, that the populations located on the edges of the study area diverge from the central populations. The pattern of population differentiation corresponds well with their geographic location and the characteristics of the sampling sites. Due to the character of iPBS markers, the observed genetic variability of populations may be explained by the genome rearrangements caused by mobilization of mobile genetic elements in the response to various stress factors. Additionally, this study demonstrates the usefulness of iPBS markers for genetic diversity studies in wild species.

Open access

Jana Nováková and Iva Melčáková

score system based on macroinvertebrates over a wide range of unpolluted running-water sites. Water Research. 1983, vol. 17, pp. 333-347. [5] JUST, T. et al. Vodohospodářské revitalizace a jejich uplatnění v ochraně před povodněmi. Praha : 3. ZO ČSOP HOŘOVICKO, EKOLOGICKÉ SLUŽBY s.r.o, AOPK ČR, MŽP ČR, 359 pp. ISBN 80-239-6351-1. [6] ZAMORA-MUNOZ, C., SAINZ-CANTERO, C., SANCHEZ-ORTEGA, A., ALBA-TERCEDOR, J. Are biological indices BMWP and ASPT and their significance regarding water quality seasonally dependent? Factors explaining their

Open access

Friđgeir Grímsson, Alexandros Xafis, Frank H. Neumann and Reinhard Zetter

reconstruction of seven continuous and 20 categorical pollen traits scored for extant Winteraceae. Supplement to Grímsson et al. „A Winteraceae pollen tetrad from the early Paleocene of western Greenland and the fossil record of Winteraceae in Laurasia and Gondwana”. http://rpubs.com/AlastairPotts/WinterIsComing . PRAGLOWSKI J. 1979. Winteraceae Lindl. World Pollen and Spore Flora, 8: 1–25. PUNT W., HOEN P.P., BLACKMORE S., NILSSON S. & LE THOMAS A. 2007. Glossary of pollen and spore terminology. Rev. Palaeobot. Palynol., 143: 1–81. RAINE J.I., MILDENHALL D

Open access

Barbara Sensuła and Sławomir Wilczyński

chronologies ( Wigley et al ., 1984 ). Ordination of the pine populations and climate-growth relationship The principal component analysis (PCA) was applied to identify the short-time factors affecting tree-ring widths. The identification of PC1 and PC2 was based on an analysis of the component scores. The variables (n=52) were site sensitivity chronologies. The cluster analysis (CA) based on Ward’s method and 1-r Pearson’s distance has been used to analyse similarity of the response of each pine population to climate elements in the 1951–2012 period. The variables (n

Open access

Armand Kasztelan

Abstract

Environmental resources and values (natural capital) should be seen as a key factor in regional competitiveness. However, little attention has been paid so far to the role of natural capital in the process of achieving competitive advantage from the territorial perspective. Therefore, the main purpose of this paper is to present the results of a study on the environmental competitiveness of Polish regions. The author’s contribution to the theory is the use of taxonomic metrics for research purposes. Based on certain predefined criteria the environmental potential of each voivodship was assessed in 2004 and 2012. For research purposes, 26 indicators of state, pressure, and environmental protection were proposed. Owing to the fact that the subset of diagnostic variables (indicators) contained elements that could not be directly aggregated, their unification was achieved using standardization formulas. The methodology proposed by the author might be used to assess environmental competitiveness in different regions or countries. The results of the performed analyses indicated that the Subcarpathian province scored highest in terms of environmental competitiveness, while Swiętokrzyskie province scored lowest.

Open access

Julita Łukomska

( i , max ) ) 2 $$\begin{array}{} \text H = \sqrt{\sum(x(i,j)\,-\,x(i,{\text {max}}))^{2} } \end{array}$$ where: HI - hierarchy index x(i, j) – standardized value of variable i for unit j (standardization performed with z-score method The z-score formula is the following: z ( i j ) = x ( j ) − x ( i ) ¯ d ( x ) ( i ) , $\begin{array}{} z(ij)=\frac{x(j)-{\overline{x(i)}}}{d(x)(i)}, \end{array}$ where z(ij) – standardized value, x(ij) – “original” value of variable i for city j, x ( i ) - mean value of the variable i for all cities, d

Open access

Patryk Orlewski

order to check the attitude of Silesians towards the co-inhabiting nationalities, respondents were asked to assess (on a scale from 1 to 5) relations between Silesians and Poles, as well as between Silesians and Germans. The relationship between Silesians and Germans got better scores: over 90% of respondents rated it between 3 and 5. One-third of them defined relations with the German people as very good ( Fig. 6 ). Among the reasons given for that were: no problems with members of the German minority, family working in Germany, and the overlapping of these two