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Abstract  

This article explores the concentration in the global plant molecular life science research output. In the past 15 years, especially the share of articles which refer to the model organism A. thaliana has increased rapidly. Citation analyses show an even greater rise in the importance of this organism. Attempts are discussed to come to a scientometric definition of model organisms. For this purpose a comparison is made with applied microbiology. However, few shared scientometric characteristics were found which could help characterise model organisms. A distinction between major economic organisms and model organisms will therefore continue to rely on qualitative data.

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Abstract  

Measurement of radon is of interest both for the health risk assessment and development of radon therapy in enclosed spaces like as caves, mines and spas. In Romania, radon therapy is not in use, yet. The development of this treatment method in mines from our country involves primarily, the evaluation of radon levels in the salt mines. In this paper, the results of radon gas measurement that were performed at Ocna Dej salt mine (Romania) are presented. The radon measurements were performed using two systems: radon monitor Pylon AB-5 system and CIS-P5M system. The average radon concentration was found to be between 9.14 ± 5.10 Bq/m3 and 31.70 ± 2.76 Bq/m3. These radon levels are lower in comparison to those reported for mines, caves or spas in other countries where radon therapy and speleotherapy is frequently in use. Radon concentration and environmental conditions from Ocna Dej salt mine are suitable for therapeutic applications.

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Abstract  

Neutron activation analysis using the k 0 standardization method (k 0-NAA) and fast neutron activation analysis using reactor fission neutrons, were used to determine the impurity concentrations in WO3, MoO3, SnO2 and TeO2 targets. The radioimpurities 124Sb, 134Cs, 60Co, 87Rb, 182Ta, 233Pa, 65Zn, 59Fe, 110mAg, 51Cr, 95Zr, 75Se and 114mIn were found in the irradiated targets and their origin either neutron capture reactions, or threshold reactions or both were identified. The specific activities of 187W, 188Re, 99mTc, 113mIn, 117mSn and 131I radioisotopes were determined. It is shown that the epithermal neutron flux significantly contributes to the isotopes characterized with high Q0 values. It is shown that the 117mSn isotope can be produced with a high specific activity using the fast neutron component of the reactor neutron spectrum.

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) is known to play many roles in enzymatic activity, and is an essential trace element for the host and pathogen ( Ong et al., 2006 ). Fe concentration decreases rapidly in response to inflammation and this can be explained as the host's defence

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Geographical concentration

The case of economics journals

Scientometrics
Author: Tove Faber Frandsen

Summary The purpose of this paper is to investigate whether geographical concentration can act as a supplement to the Journal Impact Factor (JIF). The results indicate that the use of a geographical concentration measure opens up new possibilities for analyses of the development of geographic diversion over time. In contrast to measures used in earlier studies the precise strength of the geographical concentration index as a measure of diversion is that it represents diversion as a single value that can be followed over time. The results show wider geographic distribution of European economics journals in the 1980s compared to the American economics journals whereas there seems to be no difference in geographic dispersion in the 1990s.

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Abstract  

Tritiated water is probably the most mobile manmade nuclide found in the environment. The low-energy beta decay produces few health concerns except at extremely high concentrations of tritium. However, because of the ubiquitous nature of tritiated water, when identified in the bionetwork, it can be viewed as a precursor of nuclides with greater health risks. For this reason alone it becomes desirable to determine tritium concentrations many orders of magnitude below that considered a health concern. A devise is described that eliminates the need for large water-filled chest freezers used as coolers. The enrichment cells can be employed individually or in series.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Hai-Qing Zhang, Bang-Fa Ni, Wei-Zhi Tian, Gui-Ying Zhang, Dong-Hui Huang, Cun-Xiong Liu, Cai-Jin Xiao, Hong-Chao Sun, and Chang-Jun Zhao

Abstract  

Twenty different brands of Chinese tea were analyzed for multiple trace elements, including some essential and toxic elements, by neutron activation analysis (NAA). A comparison among tea brands from China, India, US and other countries was made for the ranges and averages of concentrations for Na, K, Mn, Cu, and Br. It has been observed that the trace element contents in tea leaves are largely dependent upon the soil and the environment where the tea grows. Chinese tea is rich in Mn and Cu comparing with those of other counties surveyed, but is indigent in Na. The transference ratio for each element determined (i.e., the fraction of an element in tea leave transferred into solution when tea is leached by percolation) is also reported. Adult daily intakes of some essential and toxic elements from tea drinking were also estimated.

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345 350 Kuktaite, R., Johansson, E., Juodeikiene, G. 2000. Composition and concentration of proteins in Lithuanian wheat cultivars: relationships with bread-making quality

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Banvolgyi, Sz., Horvath, Sz., Stefanovits-Banyai, E., Bekassy-Molnar, E. & Vatai, Gy. (2009): Integrated membrane process for blackcurrant ( Ribes nigrum L.) juice concentration. Desalination , 241 , 281

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Abstract  

An important parameter for evaluating the possibilities of use of enclosed spaces (mines, caves, spas, etc.) for therapeutic purposes is the concentration of radon in different conditions of ventilation. The aim of this paper is to present the results of continuous radon gas measurement that were performed for ten days, at 20 min time intervals in different locations from Cacica salt mine (Romania) using a portable radon monitor. The average radon concentration was found to be between 96.5 ± 4.76 Bq/m3 and 20.5 ± 1.30 Bq/m3. These values are suitable for therapeutic applications and are useful for future experiments regarding the development of the radon therapy and speleotherapy in this salt mine.

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