Effect of S0/X0 ratio and acclimation on respirometry of activated sludge in the cometabolic biodegradation of phenolic compounds

Aerobic batch biodegradation experiments and respirometric analysis were performed in order to investigate the effect of S(0)/X(0) (substrate/biomass) ratio and preliminary acclimation on bi-solute biodegradation of phenolic compounds. It was shown that 2-chlorophenol (2-CP) and 2-nitrophenol (2-NP) could be cometabolically biodegraded only with acclimated biomass in the presence of phenol as growth substrate. Acclimation resulted in domination of phenol oxidizing bacteria which could induce the necessary enzymes for cometabolic transformation of 2-CP and 2-NP. Biodegradation of the cometabolic compounds occurred even after depletion of phenol at resting cell conditions. Both compounds could be successfully biodegraded by the acclimated biomass at initial substrate concentrations as high as 300 mg/L. Respirometric analysis showed that the optimum S(0)/X(0) ratio ranged between 1.5 and 5.5mg COD(eq)/mg MLSS for cometabolic substrates 2-CP and 2-NP, whereas it was as high as 8.5mg COD(eq)/mg MLSS for phenol which corresponds to a phenol concentration of about 1500 mg/L.

Adsorption reversibility and bioregeneration of activated carbon in the treatment of phenol

This study aims to clarify the effect of adsorbability, desorbability, biodegradability and activated carbon type on the extent of bioregeneration in the treatment of phenol. For this purpose, four different activated carbon types; one thermally activated and one chemically activated powdered carbon (PAC), and their granular countertypes (GAC) with similar physical characteristics were used. Adsorption isotherms showed that the thermally activated carbons, either in powdered or granular form, were better adsorbers for phenol than the chemically activated ones. However, adsorption was more irreversible in the case of thermally activated carbons. Bioregeneration of chemically activated carbons were found to be higher in accordance with their higher reversibility of adsorption showing that bioregeneration was controlled by the reversibility of adsorption. Bioregeneration efficiencies for the thermally activated carbons were much higher than their efficiencies of total desorbability. This indicated that some exoenzymatic reactions might have occurred so that phenol was bioregenerated more than expected.

Effects of sleep deprivation, nicotine, and selenium on wound healing in rats

Effects of sleep deprivation (SD), nicotine, and selenium (Se) on wound healing were studied in 50 male rats (Sprague-Dawley strain). Full-skin-thickness burns were produced in animals. Then, SD, nicotine, and Se administrations were applied to animals in different groups. Wound healing was assessed by pathological analysis of wound by counting fibroblasts, capillary vessels, polymorphonuclear leucocytes (PNLs), and by measuring radiolabeled immunoglobulin G (IgG) amount in wound area by radio-pharmaceutical and immunoscintigraphic procedures. The number of fibroblasts and capillary vessels were higher in control and Se groups than in sleep deprivation and nicotine groups, and the number of PNLs and the radiolabeled polyvalent IgG levels were higher in SD and nicotine groups than in control and Se groups. The results suggest that SD and nicotine may delay wound healing and that Se supplementation may accelerate wound healing by preventing nicotine-induced oxidative stress and lipid peroxidation.

Upgrading of the biotreatment in a pharmaceutical industry with activated carbon addition

The impact of powdered activated carbon (PAC) on the biotreatment of a chemical synthesis wastewater emerging from a pharmaceutical industry was studied. The aim of this addition was to decrease inhibitory and non-biodegradable organics. In the first step, PAC was directly added to activated sludge. In the next step, the wastewater was first contacted with PAC and then treated in an activated sludge reactor. COD, oxygen uptake rate (OUR) and ultraviolet-visible (UV-Vis) spectral measurements were carried out for the evaluation of performance. Direct PAC addition and PAC pretreatment led to similar results, but direct PAC addition was considered more practical than pretreatment with PAC. With the addition of PAC, the level of non-biodegradable matter and the colour of the wastewater were significantly reduced. In any case, the addition of PAC increased the OUR of activated sludge, indicating that inhibition could be decreased. The combined evaluation of OUR, spectral parameters and COD gave a better insight into the processes taking place than the COD parameter alone.

Right and left visual cortex areas in healthy subjects with right- and left-eye dominance

The aim of this work was to study the differences between the right- and left-visual cortices in relation to eyedness in healthy subjects. Ocular dominance was determined by means of the near-far alignment test. To assess visual cortical areas, the right and left sagittal scenograms of cranium by magnetic resonance imaging were used. To calculate the visual cortex areas by using scenograms, Cavalieri's method was used. In the subjects with right-eye dominance, the right visual cortex was larger than the left visual cortex, and vice versa in the subjects with left-eye dominance. The right and left cuneal areas were found to be larger in males than in females. In light of these results, it was concluded that the human eyes are predominantly controlled by the ipsilateral visual cortex.

[Campylobacter jejuni in patients with diarrhea]

In this study the stools 125 patients with diarrhea applied to Research Hospital of Medical School of Atatürk University and the stools of 69 healthy persons were investigated for gastroenteritis agents C. jejuni as well as Salmonella and Shigella. Of the zooparasiter agents protozoon and helminths were also investigated. We determined the mentioned agents in 28 of 125 patients (% 22.40). C. jejuni was isolated the most frequent cause of diarrhea with 8.80 percent. C. jejuni was isolated in high ratio from women more than men and from children more than adults. No bacterial infection agents were determined in control group but intestinal zooparasites were found with 18.85 percent.