ABSTRACT
STUDY DESIGN: A biomechanical study. PURPOSE: To develop a predictive model for pullout strength. OVERVIEW OF LITERATURE: Spine fusion surgeries are performed to correct joint deformities by restricting motion between two or more unstable vertebrae. The pedicle screw provides a corrective force to the unstable spinal segment and arrests motions at the unit that are being fused. To determine the hold of a screw, surgeons depend on a subjective perioperative feeling of insertion torque. The objective of the paper was to develop a machine learning based model using density of foam, insertion angle, insertion depth, and reinsertion to predict the pullout strength of pedicle screw. METHODS: To predict the pullout strength of pedicle screw, an experimental dataset of 48 data points was used as training data to construct a model based on different machine learning algorithms. A total of five algorithms were tested in the Weka environment and the performance was evaluated based on correlation coefficient and error matrix. A sensitive study of various parameters for obtaining the best combination of parameters for predicting the pullout strength was also preformed using the L9 orthogonal array of Taguchi Design of Experiments. RESULTS: Random forest performed the best with a correlation coefficient of 0.96, relative absolute error of 0.28, and root relative squared error of 0.29. The difference between the experimental and predicted value for the six test cases was not significant (p >0.05). CONCLUSIONS: This model can be used clinically for understanding the failure of pedicle screw pullout and pre-surgical planning for spine surgeon.
ABSTRACT
OBJECTIVE@#To evaluate in vitro antimicrobial and antioxidant activities of methanolic extract of Jasminum humile (J. humile) leaves extract.@*METHOD@#Methanolic extract of J. humile was evaluated for its antimicrobial activity by using agar well diffusion method & their possible antioxidant assay by two complementary test systems, namely DPPH and hydrogen peroxide scavenging activity. These various antioxidant activities were compared to standard antioxidants such as ascorbic acid for both the tests.@*RESULTS@#In the DPPH & hydrogen peroxide scavenging activity, the IC(50) value of methanol extract was 70.43 μg/mL & 60.79 μg/mL respectively. Further, the extract showed inhibitory activity for Gram-positive and negative bacteria at different concentrations. The maximum antibacterial activity of extract was exhibited against Staphylococcus aureus (S. aureus) at concentration 50 mg/mL when compared with ciprofloxacin@*CONCLUSIONS@#These results clearly indicate that J. humile is effective in scavenging free radicals and has the potential to be a powerful antioxidant. Thus, the results obtained in the present study indicate that J. humile leaves extract could be considered as a potential source of natural antioxidants and that could be used as an effective source against bacterial diseases.