Experimental and mathematical modeling studies on Cr(VI) reduction by CRB, SRB and IRB, individually and in combination

Cr(VI) reduction studies were carried out with chromium reducing bacteria (CRB), sulphate reducing bacteria (SRB) and iron reducing bacteria (IRB), individually and in combination. Biokinetic parameters such as maximum specific growth rate (micro(max)), half saturation constant (K(s)), yield coefficient (Y(T)) and inhibition coefficient (K(i)) for individual cultures were evaluated. A mathematical model was proposed for simulating the chromium reduction, COD utilization and biomass growth, by individual cultures as well as by a combination of two or three different cultures, for different initial Cr(VI), SO(4)(2-) and Fe(III) concentrations. The biokinetic parameters evaluated from one set of experiments for individual cultures were utilized in all the validation studies. The performance of the mathematical model in terms of the dimensionless modified coefficient of efficiency (E) indicated that the proposed model simulates the system behavior very well.

Unilateral atrophoderma vermiculatum

Atrophoderma vermiculatum is an autosomal dominant disorder with small pitted scars over cheek and forehead. A 25-year-old male had multiple 1-2 mm sized pitted scars with ridges producing a reticulated honeycomb appearance on the left cheek since childhood. The lesions were unilateral and there was no other family member with similar lesions.

Atrichia with Cysts and Papules

A robust, intelligent male aged 32 years had atrichia with cystic lesions. Scanty hairs were present at birth on the scalp and were shed in the course of a few weeks. Multiple papular and cystic swelling started appearing 10 years back and 'were seen over the shoulders, axihae and the elbows. Nails although normal were racquet shaped while the teeth were normal. The mode of inheritance of this rare condition has not yet been established.