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Purpose The purpose of this paper is to study the integration between fused deposition modeling (FDM) technology and abrasive flow machining process to improve the surface quality of FDM printed parts. FDM process has some limitations in terms of accuracy and surface finish. Hence, post-processing operations are essential to increase the quality of the part. Design/methodology/approach Initially, a sustainable polymer abrasive gel-based media (SPAGM) using natural polymer and natural additives (waste vegetable oil) was prepared using different combinations of (abrasive mesh size, percentage of abrasives and percentage of liquid synthesizer); then the characterization of media was done to check various properties. As media is an essential part in the process which helps in increase the surface finish, it needs to have some desired characteristics such as the following: the developed SPAG needs to hold the abrasives; its viscosity has to be medium so that it can easily flow through the machine; and its thermal stability caused by the increase in the temperature during various cycles of operation. For that, it is characterized rheologically as well as thermally to find its various properties. Findings Experiments were performed on FDM-printed parts using an L9 orthogonal array with different parameters to find their effect on the workpiece. Scanning electron microscope images of SGAPM showed sharp edges of abrasive particles and bonding pattern between polymer chain molecules. Good surface finish and material removal rate (MRR) was observed at high pressure and long finishing time with 50 per cent abrasive concentration. Originality/value The authors confirm that this work is original and has neither been published elsewhere nor is it currently under consideration for publication elsewhere.

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The interaction of genetic and environmental factors can determine individual susceptibility to various cancers. We studied the influence of NAT2 and codon 72 p53 polymorphisms on 151 patients with lung cancer and an equal number of matched population controls. Polymorphisms of NAT2 and p53 were determined by PCR-RFLP techniques. The results were analyzed using logistic regression analysis. A statistically significant relationship between NAT2*5 and NAT2*6 alleles and lung cancer risk was observed. In addition, the population with slow acetylator alleles for NAT2*5 and NAT2*6 had a significantly higher risk of lung cancer compared with rapid acetylator alleles both in smokers and nonsmokers. The combined genotype of heterozygous arginine (Arg)/proline (Pro), Pro/Pro, and slow acetylator alleles of NAT2*5 and NAT2*6 showed higher, although not significant, risk of lung cancer compared with Arg/Arg and rapid acetylator alleles of NAT2*5 and NAT2*6. In conclusion, these findings suggest that the influence of NAT2 genotype, alone or in combination with p53 genotype, may confer increased susceptibility to lung cancer.