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Batch experiments were conducted with dead and living Arthrobacter viscosus biomass for Cr(VI) removal from aqueous solution. Both dead and living cells successfully reduced Cr(VI) to Cr(III) from aqueous solution in highly acidic pH (pH 1 and 2) with an efficiency of 100% for aqueous solutions having the initial concentrations of Cr(VI) lower than 100 mg/L. Langmuir isotherm and kinetic models based on reduction could simulate chromium removal at 5 and 8 g/L biosorbent dosages and in highly acidic pH conditions (pH = 1-2). Further, the potential use of the Arthrobacter viscosus biomass was examined in an open system, where Cr(VI) removal from aqueous solution was performed by a bacterial biofilm supported on a new type of polyethylene supports. The experiment showed a favorable uptake of chromium ions bound to the biomass, of 20.37 mg/g, with high potential for scaling up. This study showed that the reduction of toxic Cr(VI) to the less toxic Cr(III) by Arthrobacter viscosus, in batch and continuous modes is an efficient and promising technique for wastewaters polluted with chromium. ; This paper was elaborated with the support of BRAIN project Doctoral scholarships as an investment in intelligence - ID 6681, financed by the European Social Found and Romanian Government and with the support of a grant of the Romanian National Authority for Scientific Research, CNCS – UEFISCDI, project number PN-II-ID-PCE-2011-3-0559, Contract 265/2011. H. Figueiredo is thankful to "FCT – Fundação para a Ciência e Tecnologia" for the financial support through the concession of PhD grant SFRH/BD/28201/2006. ...

In order to monitor progress with respect to gender equality in European Union member states, indices are extremely useful. Existing indices are, however, not appropriate because they do not focus exclusively on gender (in)equality and have not been created to be used at the European level. Therefore a European Union Gender Equality Index is presented in this article. Based on the universal caregiver model as outlined by Fraser (1997), the index is composed of four dimensions: equal sharing of paid work, money, decision-making power and time. With regard to the applied methodology, the index is constructed in such a way that the value indicates the actual distance from a situation of full equality. The empirical results show that full equality is still a long way off. Finland, Sweden and Denmark display the highest overall performance, whereas the southern countries — Greece, Cyprus, Malta, Spain and Italy — perform rather poorly.

The widespread of the World Wide Web has resulted in a high volume of volunteered generated information using different formats including text, photography and video. The technological advances of recent years enabled the emergence and the popularization of various mobile devices equipped with GPS and connectivity to the Internet. This scenario contributed to the advent of several location-based applications and aroused the interest of many users in the geographical context of the information. An example of such applications are the Location-Based Social Networks (LBSN), in which the users interact with information classified by geographic region, as in the context of Smart Cities, in which citizens can interact pinning their criticisms, opinions and comments on various topics related to their city or neighborhood. The LBSNs have increasingly attracted the interest of the population and have consequently registered an increase in both the number of users interacting and the volume of shared information. This popularity brings up concerns about scalability, since it is essential to provide an environment that maintains the users active and motivated for contributing. Thus, the LBSNs must ensure acceptable response times, especially in spatial queries performed by their users, otherwise such applications may collapse due to the abandonment of their faithful users. Among several proposals of LBSNs in the community, it is still difficult to find out approaches concerned in scalability. In this context, this paper proposes an approach based on Big Data technologies to provide scalability in LBSNs and thus handle large volumes of spatial data. Our approach exploits NoSQL databases, the Map/Reduce technique and the development of extensions for indexing and querying Spatial Big Data.