Comparative role of charcoal, biochar, hydrochar and modified biochar on bioavailability of heavy metal(loid)s and machine learning regression analysis in alkaline polluted soil.

Pot experiment was performed aimed to assess the comparative role of charcoal, biochar, hydrochar and thiourea-vegetable modified biochar at 1 and 2 % doses, and <1 mm particle size on the bioavailability of Cd, Pb, As, Ni, Cu and Zn, and enhance NPK, and mustard growth in a slightly alkaline polluted soil. Furthermore, machine learning method was used to examine the systematic evaluation of the impact of feature selection based on Pearson's correlation on the performance of the linear regression model. The results revealed that maximum fresh and dry biomass of mustard was observed by 26.38 and 38.18 % with hydrochar 1 %, whereas lemon biochar at 2 % reduced fresh and dry biomass up to 34.0 and 53.0 % than control. The immobilization of Cd and Pb was observed by 83.70 and 71.15 % with thiourea-vegetable modified biochar at 2 %, As 71.62 % with hydrochar 2 %, Ni 80.84 % with thiourea-vegetable modified biochar 2 %, Cu 66.32 % with and Zn 36.30 % with thiourea-vegetable modified biochar at 2 % than control. However, the maximum mobilization of Cu in soil was observed by 30.3 % with lemon biochar 2 %, similarly for Zn 37.36 % with hydrochar 2 % as compared with other treatments. The phyto-availability of Cd, Pb, As and Cu in the mustard shoot and root biomass was reduced except Ni and Zn in soil than control. It was observed that using the machine learning regression analysis approach, variability in treatments effectiveness is evident across different feature correlation thresholds. This study clearly shows that the beneficial role of studied amendments on mustard growth and reduced bioavailability of heavy metal(loid)s and enhance primary macronutrients in alkaline polluted soil. It is suggested that future studies may be conducted on combined application of studies amendments on plant growth, immobilization of heavy metal(loid)s in multi-metal polluted soil under different field conditions.

Results Of Immediate Facial Nerve Reconstruction In Patients Undergoing Parotid Tumour Resection.

BACKGROUND: Facial nerve is usually sacrificed in total parotidectomy. The objective of this study is to present results of immediate reconstruction of facial nerve in total parotidectomy cases where facial nerve is sacrificed. METHODS: This is a prospective study done in patients who had total parotidectomy including facial nerve and immediate reconstruction was done with inter-positional nerve grafts (sural n=12 and greater auricular n=10) from December 2017 till February 2018 by single surgeon (MR). Wounds were closed primarily (n=15), local flap (n=2) and free flap (n=5). Clinical evaluation was done at four months minimum follow up (those operated in January to February 2018) and eight months maximum follow up (those operated in December 2017), for facial nerve functional recovery using House and Brackmann grading system by single author (MR). RESULTS: Total of 22 (male n=7, female n=15) patients included in study from December 2017 till February 2018. Sural nerve grafts were used in 54% (n=12) and greater auricular nerve grafts in 45% (n=10) patients for reconstruction of facial nerve. On clinical evaluation using House and Brackmann grading system, showed grade V (n=4), grade IV (n=7), grade III (n=8) and grade II (n=3) repairs. CONCLUSIONS: Although primary end to end facial nerve repair is ideal but in situation where a significant segment of nerve is lost or where the repair is under tension, inter-positional nerve grafting is a simple and reliable reconstructive technique with good outcomes.