SUMMARYPurpose: This study examines whether magnetoencephalographic (MEG) coherence imaging is more sensitive than the standard single equivalent dipole (ECD) model in lateralizing the site of epileptogenicity in patients with drug-resistant temporal lobe epilepsy (TLE). Methods: An archival review of ECD MEG analyses of 30 presurgical patients with TLE was undertaken with data extracted subsequently for coherence analysis by a blinded reviewer for comparison of accuracy of lateralization. Postoperative outcome was assessed by Engel classification. MEG coherence images were generated from 10 min of spontaneous brain activity and compared to surgically resected brain areas outlined on each subject's magnetic resonance image (MRI). Coherence values were averaged independently for each hemisphere to ascertain the laterality of the epileptic network. Reliability between runs was established by calculating the correlation between epochs. Match rates compared the results of each of the two MEG analyses with optimal postoperative outcome.Key Findings: The ECD method provided an overall match rate of 50% (13/16 cases) for Engel class I outcomes, with 37% (11/30 cases) found to be indeterminate (i.e., no spikes identified on MEG). Coherence analysis provided an overall match rate of 77% (20/26 cases). Of 19 cases without evidence of mesial temporal sclerosis, coherence analysis correctly lateralized the side of TLE in 11 cases (58%). Sensitivity of the ECD method was 41% (indeterminate cases included) and that of the coherence method 73%, with a positive predictive value of 70% for an Engel class Ia outcome. Intrasubject coherence imaging reliability was consistent from run-to-run (correlation >0.90) using three 10-min epochs. Significance: MEG coherence analysis has greater sensitivity than the ECD method for lateralizing TLE and demonstrates reliable stability from run-to-run. It, therefore, improves upon the capability of MEG in providing further information of use in clinical decisionmaking where the laterality of TLE is questioned.

Zirconia and 10%, 20%, and 30% cerium-doped zirconia nanoparticles (ZCO), ZCO-1, ZCO-2, and ZCO-3, respectively, were prepared using auto-combustion method. Binary nanohybrids, ZrO2@rGO and ZCO-2@rGO (rGO = reduced graphene oxide), and ternary nanohybrids, ZrO2@rGO@MoS2 and ZCO-2@rGO@MoS2, have been prepared with an anticipation of a fruitful synergic effect of rGO, MoS2, and cerium-doped zirconia on the tribo-activity. Tribo-activity of these additives in paraffin oil (PO) has been assessed by a four-ball lubricant tester at the optimized concentration, 0.125% w/v. The tribo-performance follows the order: ZCO-2@rGO@MoS2 > ZrO2@rGO@MoS2 > ZCO-2@rGO > ZrO2@rGO > MoS2 > ZrO2 > rGO > PO. The nanoparticles acting as spacers control restacking of the nanosheets provided structural augmentation while nanosheets, in turn, prevent agglomeration of the nanoparticles. Doped nanoparticles upgraded the activity by forming defects. Thus, the results acknowledge the synergic effect of cerium-doped zirconia and lamellar nanosheets of rGO and MoS2. There is noncovalent interaction among all the individuals. Analysis of the morphological features of wear-track carried out by scanning electron microscopy (SEM) and atomic force microscopy (AFM) in PO and its formulations with various additives is consistent with the above sequence. The energy dispersive X-ray (EDX) spectrum of ZCO-2@rGO@MoS2 indicates the existence of zirconium, cerium, molybdenum, and sulfur on the wear-track, confirming, thereby, the active role played by these elements during tribofilm formation. The X-ray photoelectron spectroscopy (XPS) studies of worn surface reveal that the tribofilm is made up of rGO, zirconia, ceria, and MoS2 along with Fe2O3, MoO3, and SO42− as the outcome of the tribo-chemical reaction.

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For enhancement of the tribological activity of nanolamellar graphene oxide (GO), its nucleophilic substitution was performed by methionine to yield methionine-functionalized reduced graphene oxide (M-rGO). Further, noncovalent functionalization of another tribo active material, nanolamellar MoS2, was accomplished by lanthanum (7%)-doped yttria nanoparticles (NPs), resulting in the formation of a nanocomposite, (La-Y2O3)-MoS2. The doped NPs were deliberately chosen for this purpose because there was a clear increase in the wear/friction-reducing tendencies of yttria after doping with lanthanum. For further advancement of the tribological activity, a ternary nanocomposite (La-Y2O3)-MoS2-(M-rGO) was synthesized containing lanthanum-doped yttria NPs, M-rGO, and MoS2 nanosheets. The NPs, nanosheets, and composites have been characterized by powder X-ray diffraction, high-resolution scanning electron microscopy (HR-SEM), transmission electron microscopy, and Raman spectroscopy. X-ray photoelectron spectroscopy (XPS) was employed to study the chemical states of different elements in (La-Y2O3)-MoS2-(M-rGO). The tribological properties of well-characterized composites were evaluated in paraffin oil (PO) using a four-ball tester according to ASTM D4172 and ASTM D5183 standards at the optimized concentration, 0.20% (w/v). There was incremental evolution in the tribological properties from plain PO through Y2O3, MoS2, M-rGO, La-Y2O3, and (La-Y2O3)-MoS2 and finally to (La-Y2O3)-MoS2-(M-rGO). Here functionalization of GO has invigorated its structure. Both nanosheets coordinated to control agglomeration of the NPs. The NPs prevented the nanosheets from restacking. SEM and atomic force microscopy images of the wear scar validated the results of tribological tests. The presence of yttrium, lanthanum, sulfur, and molybdenum besides carbon, nitrogen, and oxygen in the energy-dispersive X-ray spectrum of the worn surface in the presence of PO blended with (La-Y2O3)-MoS2-(M-rGO) is indicative of its strong adsorption on the surface. On the basis of XPS studies of the wear track, the constituents of the tribofilm could be identified as adsorbed rGO, yttria, lanthanum oxide, and MoS2 in addition to tribochemically produced Fe2O3, MoO3, and SO4 2–. The mutualistic approach of the constituents has yielded splendid results.