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The present study aimed to implement a sustainable machining method to improve energy efficiency in helical milling (HM) of AISI 1020. Therefore, ultrasonic vibration is integrated with conventional helical milling to reduce cutting forces. A model was developed for power consumption in terms of cutting forces in x, y and z directions, tangential and axial feed speeds. Series of plain and ultrasonic vibration helical milling (UVHM) experiments are conducted using 10 and 8 mm diameter mill cutters at different working conditions and experimental results for cutting forces are collected. Formation of chip and its geometry are investigated using the cutting trajectories of the bottom cutting edges of the cutter. Cutting forces and power consumption are estimated related to chip geometry in plain and UVHM processes and compared. In UVHM, the axial force is reduced by around 47% as the ultrasonic vibration is applied in the axial direction and the power consumption is reduced by 34%. The results showed that ultrasonic vibration has a significant effect on chip morphology, cutting force and power consumption, indicating that ultrasonic vibration assisted machining has a wide application in manufacturing. The process parameters are optimised as 2000 rpm of cutter rotational speed, 156 rpm of cutter orbital speed and 0.3 mm of axial depth of cut using 8 mm diameter cutter and the chip thickness, chip depth and power consumption are found to be 0.3969 mm, 0.2665 mm and 835.6 W respectively at optimal working condition.

Titanium alloys are the difficult to cut metals due to their low thermal conductivity and chemical affinity with tool material. Since the tool vibration is a replica of tool wear and surface roughness, the present study has proposed a methodology for estimating tool wear and surface roughness based on tool vibration for milling of Ti-6Al-4V alloy using cemented carbide mill cutter. Experiments are conducted at optimum levels of cutting speed, feed per tooth, and depth of cut, and experimental results for the tool vibration, tool wear, and surface roughness are collected until the flank wear reached 0.3 mm (ISO3685:1993). In the next stage, an optimization model of grey prediction GM(1,N) system and support vector machine (SVM) are used and estimated tool wear and surface roughness related to tool vibration. The predicted values of tool wear and surface roughness are compared with the experimental results. The optimization model of GM(1,N) predicted the tool wear and surface roughness with an average error of 3.03% and as 0.7% respectively while the SVM predicted with an average error of 7.67% and 4.45%, respectively.

A recent discovery of aromatase crystal structure triggered the efforts to design novel aromatase inhibitors for breast cancer therapy. While correlating docking scores with inhibitory potencies of known ligands, feeble robustness of scoring functions toward prediction was observed. This prompted us to develop new prediction models using stepwise regression analysis based on consensus of different docking and their scoring methods (GOLD, LIGANDFIT, and GLIDE). Quantitative structure-activity relationships were developed between the aromatase inhibitory activity (pIC(50) ) of flavonoid derivatives (n=39) and docking scores and docking descriptors. QSAR models have been validated internally [using leave-one-out cross-validated r(2)(cv) (LOO-Q2))] and externally to ensure the predictive capacity of the models. Model 2 [M2] developed using consensus of docking scores of scoring functions viz. ASP, potential of mean force and DOCK Score (r(2)(cv)=0.850, r(2) = 0.870, r(2)(pred) = 0.633, RMSE = 0.363 μm, r(2)(m(test)) =0.831, r(2)(m(overall)) =0.832) was found to be better in predicting aromatase inhibitory potency (pIC(50) ) compared to the Model 1 [M1] based on docking descriptors (r(2)(cv)= 0.848, r(2) = 0.825, r(2)(pred) =0.788, RMSE=0.421μm, r(2)(m(test)) =0.808, r(2)(m(overall)) =0.821). It has been observed that the natural flavonoids and their derivatives were less potent compared to these scaffolds with imidazolylmethyl substitution owing to the interaction of nitrogen atom of the imidazole ring toward the heme (Fe(3+) ) of the aromatase. Results confirm the potential of our methodology for the design of new potent non-steroidal aromatase inhibitors.

A recent discovery of aromatase crystal structure triggered the efforts to design novel aromatase inhibitors for breast cancer therapy. While correlating docking scores with inhibitory potencies of known ligands, feeble robustness of scoring functions toward prediction was observed. This prompted us to develop new prediction models using stepwise regression analysis based on consensus of different docking and their scoring methods (GOLD, LIGANDFIT, and GLIDE). Quantitative structure-activity relationships were developed between the aromatase inhibitory activity (pIC(50) ) of flavonoid derivatives (n=39) and docking scores and docking descriptors. QSAR models have been validated internally [using leave-one-out cross-validated r(2)(cv) (LOO-Q2))] and externally to ensure the predictive capacity of the models. Model 2 [M2] developed using consensus of docking scores of scoring functions viz. ASP, potential of mean force and DOCK Score (r(2)(cv)=0.850, r(2) = 0.870, r(2)(pred) = 0.633, RMSE = 0.363 μm, r(2)(m(test)) =0.831, r(2)(m(overall)) =0.832) was found to be better in predicting aromatase inhibitory potency (pIC(50) ) compared to the Model 1 [M1] based on docking descriptors (r(2)(cv)= 0.848, r(2) = 0.825, r(2)(pred) =0.788, RMSE=0.421μm, r(2)(m(test)) =0.808, r(2)(m(overall)) =0.821). It has been observed that the natural flavonoids and their derivatives were less potent compared to these scaffolds with imidazolylmethyl substitution owing to the interaction of nitrogen atom of the imidazole ring toward the heme (Fe(3+) ) of the aromatase. Results confirm the potential of our methodology for the design of new potent non-steroidal aromatase inhibitors.

A quick, efficient and convenient method for the regiospecific reductive ring opening of 4,6-O-benzylidene acetals of O-/S-alkyl/aryl glycosides of mono- and disaccharides, leading to the exclusive formation of the corresponding 6-O-benzyl ethers, using sodium cyanoborohydride in the presence of molecular iodine, is reported. It has been observed that common protecting groups such as ethers and esters are well tolerated under the conditions studied. The reaction was proved unsuccessful when applied to a glucosamine-derived benzylidene acetal.