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    Antimicrobial Resistance of Gram-Negative Isolates from Intensive Care Units in Turkey: Comparison to Previous Three Years
    (E I F T Srl, 2000) Yücesoy, M.; Yuluğ, N.; Kocagöz, S.; Ünal, S.; Çetin, S.; Çalangu, S.
    Resistance rates to selected antibiotics of Gram-negative bacteria isolated from intensive care units (ICU) of 16 Turkish hospitals during 1998 were evaluated and compared to data from the previous 3 years. Antibiotic susceptibilities to imipenem, ceftazidime, ceftazidime-clavulanate, cefoperazone-sulbactam, ceftriaxone, cefepime, cefodizime, cefuroxime, piperacillin-tazobactam, ticarcillin-clavulanate, gentamicin, amikacin and ciprofloxacin were determined by Etest, A total of 1,404 isolates from 1,060 patients were collected, mainly from urinary and respiratory tracts. As in the previous 3 years, Pseudomonas spp, was the most frequently isolated Gram-negative species (29.7%), followed by Escherichia coli, Acinetobacter and Klebsiella spp, Imipenem was the most active in vitro agent (73.4% susceptible), followed by ciprofloxacin (60.6%), cefoperazone-sulbactam (58.7%), cefepime (56.7%), piperacillin-tazobactam (55.0%) and amikacin (54.7%), In 1996, a decline in susceptibility rates of all antibiotics was evident. With the exception of imipenem, resistance to which remained stable, rates somewhat increased in 1997. In 1998, susceptibility to imipenem and cefepime remained stable, amikacin resistance tended to increase and susceptibility rates to other antibacterials showed a favorable increase. These results may in part be due to the implementation of a surveillance program and increased understanding of the magnitude of the resistance problem.
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    Equilibrium Studies for the Sorption of Zinc and Copper From Aqueous Solutions Using Sugar Beet Pulp and Fly Ash
    (Elsevier Science Bv, 2006) Pehlivan, E.; Çetin, S.; Yanık, B. H.
    In the present work, the abilities of native sugar beet pulp (SBP) and fly ash (FA) to remove copper (Cu2+) and zinc (Zn2+) ions from aqueous solutions were compared. The SBP and FA, an industrial by-product and solid waste of sugar industry, were used for the removal of copper and zinc from aqueous water. Batch adsorption experiments were performed in order to evaluate the removal efficiency of SBP and lignite-based FA. The effect of various operating variables. i.e. initial pH, adsorbent dose, initial metal ion concentration, and time on adsorption of copper and zinc onto the SBP and FA, has been studied. The sorption process was relatively fast and equilibrium was reached after about 60 min of contact. As much as 60-97% removal of copper and zinc for SBP and FA are possible in about 60 min, respectively, under the batch test conditions. Uptake showed a pH-dependent profile. The overall uptake for the SBP is at a maximum at pH 5.5 and gives up to 30.9 mg g(-1) for copper and at pH 6.0 and gives 35.6 mg g(-1) for zinc for SBP which seems to be removed exclusively by ion exchange and physical sorption. Maximum adsorption of copper and zinc occurred 7.0 and 7.84 mg g(-1) at a pH value of 5.0 and 4.0 for FA, respectively. A dose of 8 g l(-1) of SBP and 8 g l(-1) FA were sufficient for the optimum removal of both the metal ions. The sorption data were represented by the Freundlich for SBP and the Langmuir and Freundlich for FA. The sorption data were better represented by the Langmuir isotherm than by the Freundlich one for FA in the adsorption of zinc ion, suggesting the presence of low ionic strength or low concentration of Na and Cl ions does not have that the monolayer sorption. mainly due to ion exchange a significant effect on the adsorption of these metals by SBP and FA. The SBP and FA are shown to be effective metal adsorbents for these two metals.