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a b s t r a c tThe cement industry is one of the leading producers of anthropogenic greenhouse gases, of which CO 2 is the most significant. Recently, researchers have invested a considerable amount of time studying ways to improve energy consumption and pollutant formation in the overall cement manufacturing process. One idea involves dividing the calcination and clinkering processes into two separate furnaces. The calcination process is performed in a calciner while the clinkering process takes place in a rotary kiln. As this is new technology in the cement manufacturing process, calciners are still in the research and development phase. The purpose of this paper is to demonstrate the potential of CFD to support the design and optimization of calciners, whose use appears to be essential in reduction of CO 2 emission during cement production. The mathematical model of the calcination process was developed, validated and implemented into a commercial CFD code, which was then used for the analysis. From the results obtained by these simulations, researchers will gain an in-depth understanding of all thermo-chemical reactions in a calciner. This understanding can be used to optimize the calciner's geometry, to make production more efficient, to lower pollutant formation and to subsequently reduce greenhouse gas emissions.

The new GenoType MTBDRsl assay (Hain Lifescience) detects mutations most frequently associated with resistance to fluoroquinolones (FLQ), aminoglycosides/cyclic peptides (AG/CP), and ethambutol (EMB) and thus, enables rapid identification of extensively drug-resistant (XDR) Mycobacterium tuberculosis strains. A set of 19 multidrug-resistant (MDR) strains isolated in Serbia in 2011 was tested by the MTBDRsl assay and by conventional drug susceptibility testing (DST). The sensitivity and specificity of the MTBDRsl assay were as follows: 100% for both for FLQ; 100% for both for AG/ CP; and 58.3% and 85.7%, respectively, for EMB. The sensitivity for detection of XDR strains was 100%. Mutations in the gyrA, rrs, and embB genes established in local M. tuberculosis strains resistant to the respective drugs have been reported as the most prevalent in other studies as well. We recommend the MTBDRsl assay as a screening test for the preliminary detection of XDR-TB cases in Serbia, but not as a replacement of the conventional second-line DST. [Projekat Ministarstva nauke Republike Srbije, br. 175039