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Optimization in turning means determination of the optimal set of the machining parameters to satisfy the objectives within the operational constraints. These objectives may be the minimum tool wear, the maximum metal removal rate (MRR), or any weighted combination of both. The main machining parameters which are considered as variables of the optimization are the cutting speed, feed rate, depth of cut, and nose radius. The optimum set of these four input parameters is determined for a particular job-tool combination of 7075Al alloy-15 wt. % SiC (20–40 μm) composite and tungsten carbide tool during a single-pass turning which minimizes the tool wear and maximizes the metal removal rate. The regression models, developed for the minimum tool wear and the maximum MRR were used for finding the multiresponse optimization solutions. To obtain a trade-off between the tool wear and MRR the, a method for simultaneous optimization of the multiple responses based on an overall desirability function was used. The research deals with the optimization of multiple surface roughness parameters along with MRR in search of an optimal parametric combination (favorable process environment) capable of producing desired surface quality of the turned product in a relatively lesser time (enhancement in productivity). The multi-objective optimization resulted in a cutting speed of 210 m/min, a feed of 0.16 mm/rev, a depth of cut of 0.42 mm, and a nose radius of 0.40 mm. These machining conditions are expected to respond with the minimum tool wear and maximum the MRR, which correspond to a satisfactory overall desirability.

One hundred patients with warts (Verruca vulgaris of hands-33; feet-16, hands and feet 10; palmar warts-17 and plantar warts-24) were treated with salicylic acid (16.5%) and lactic acid (16.5%) in flexible collodion wart (SAL) paint. The wart paint was applied twice a week for 3 months. Good response was seen in 82.1% of warts on hands. 46.7% of palmar warts, 54.5% of warts on feet, 84.2% of plantar warts and 57.1% of warts on hands and feet. Overall success rate was 70%. Eighty percent patients completed the study. No adverse effects were observed. During 6 months post treatment follow up recurrence of warts occurred in 11.7% of patients.

Dyschromatosis universalis hereditaria is a common disorder in Japan. We report a case in an Indian woman with no family history of the disorder.

Patch test was evaluated for the identification of causative agent in cutaneous eruptions due to antiepileptics. Patch tests were carried out in twenty patients and ten controls with carbamazepine, phenytoin sodium, phenobarbitone and sodium valproate. Sodium valproate was found tobe irritant in 1 and 5% concentration and further dilution is recommended for patch testing. Patch test was positive in 14 (70%) patients and in 7 with suspected drug alone, and remaining 7 were positive with more than one antiepileptic drug. We recommended patch test for identification of causative drug in rashes due to antiepileptics.

Autologous transplantation of melanocyte/melanocytes bearing epidermis for vitiligo can be done by mini-punch grafting (MPG), suction blister epidermal grafting (SBEG), thin split -thickness skin grafting (TSTG), transplantation of basal cell layer enriched suspension and cultured epithelial/melanocyte transplantation. To date no comparative study of these transplantation procedures has been published. Comparison of different studies carried out at different centers may be difficult in the absence of uniform evaluation criteria. In most of the published studies, the results were evaluated in terms of extent of pigmentation. Complictions and color match were evaluated separately. This approach, however, may not give a fair idea about the results. We have developed a scoring system with holistic approach considering the extent of pigmentation, color match and the complications of both the donor and the recipient areas, all taken together. In the scoring system, the score for individual criteria was multiplied with a factor, the value of which was decided on the basis of relative importance of each criteria. The use of this scoring system is exemplified in twelve patients who underwent TSTG, SBEG and MPG. In the scoring system the results were judged as excellent and fair in 3 patients each, as good in 4 patients and as poor in 2 patients.

Three women with large, mutilating genital ulcers of long duration, destroying almost the lower half of the external genitalia, are reported. They had a history of recurrent oral ulcers as well. All patients had been diagnosed as having ′genital ulcer syndrome′ in the past and had been treated with antimicrobials. Histopathology of the biopsy from the margin of the ulcer revealed features of leukocytoclastic vasculitis. Considering the history, clinical features and histology, a diagnosis of bipolar aphthosis was made in all patients. All patients responded well to immunosuppressive therapy. The cases are reported because of the presence of genital ulcers of an unusually large size, mutilating character and their close similarity to genital ulcers due to sexually transmitted diseases, especially genital herpes and donovanosis.

Metallic composite materials reinforced with ceramic particles or short fibres, also known as discontinuously reinforced metal matrix composites (MMCs), have been studied over the past few decades. There is a strong potential for these materials to replace existing metallic systems due to their enhanced mechanical properties (especially higher specific stiffness and strength). Performance of automobile and aircraft parts can be improved through either a reduction in absolute weight or an increase in strength to weight ratio. 7075 Al alloy reinforced with 10 vol. % SiC particles of size 20 to 40 μm was prepared by using stir casting process. The values of Young's modulus and peak frequency for 7075 Al alloy and 10% SiC composite were found out by using dynamic elastic property analyser. Porosity of 10% SiC composite was also calculated. Test results indicate that value of Young's modulus and peak frequency for composite increases 24.898% and 7.38% respectively on average. This is due to addition of 10% SiC particles. The porosity of composite is found to be 3.16%.

In this paper an attempt has been made to achieve a set of values of stir casting process variables that may yield optimum porosity to the 7075 Al alloy with 10% SiC composite. The effect of selected process variables on the porosity of 7075 Al alloy 10% SiC composite and subsequent optimal settings of the variables have been obtained using Taguchi method. The results indicate that the holding time, holding temperature and stirring speed are the significant variables. Stirring time is insignificant variable. As the holding time, holding temperature and stirring time increases the porosity decreases. When the stirring speed increases, porosity increases. The predicted optimal value of porosity is 4.71%.