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The balance between comprehensive intraoperative neurophysiological monitoring (IONM) for both upper and lower limbs while ensuring the reliability of motor evoked potentials (MEPs) is paramount in motor area surgery. It is commonly difficult to obtain good simultaneous stimulation of both upper and lower limbs. A series of factors can bias MEP accuracy, and inappropriate stimulation intensity can result in unreliable monitoring. The presented IONM technique is based on the concurrent use of both transcranial and cortical strip electrodes to facilitate simultaneous monitoring of both upper and lower limbs at optimized stimulation intensities to increase IONM accuracy during motor area surgery. Ten nonconsecutive motor area tumors were studied. Good visualization of both limbs was observed in the series at a low amperage (1.2 mA from the strip electrode and 165.3 mA from the transcranial electrode). Our analysis confirms concordance between the IONM data and postoperative outcomes. An MEP reduction >20% and >50% correlated with postoperative modified Rankin scale score changes without false-negative IONM findings. The technique was demonstrated to be accurate in providing a good simultaneous neurophysiological evaluation of both upper and lower limbs with an optimized and stimulation amplitude. The technique results in a low encumbrance of electrodes in the surgical field. Our results have confirmed the "proof of concept," its reliability and feasibility. [ABSTRACT FROM AUTHOR]

The gasification of agro-industrial residues has been identified as a viable alternative for energy generation, acting simultaneously as a solution for the final disposal of these wastes. Knowing the kinetics of the gasification reaction is crucial to the comprehension of the mechanisms and the phenomena involved in the process, and the development and optimization of industrial gasifiers. Accordingly, this study aims to examine, based on four kinetic models, the CO2 gasification behavior of three biomass chars prepared from apple pomace, spent coffee grounds and sawdust, and to associate the results with differences in the ash composition of the samples. The biochars were obtained from pyrolysis under N2, in a fixed-bed tubular quartz reactor, with an average heating rate of 12 K min−1 and a residence time of 60 min at the final temperature of 873 K. Biochars were isothermally gasified in a thermogravimetric analyzer with CO2, at atmospheric pressure, at temperatures of 1033, 1083 and 1133 K, in the kinetically controlled regime. From the characterization of raw biomasses, it was found that the apple pomace had the highest amount of potassium, and its biochar was the most reactive. Also, it was observed an increase in the gasification rates in the higher conversion region for all biochars. Concerning these reactivity profiles, the inorganic components were more important to the gasification behavior than the biomass lignocellulosic matter. For all biochars, the semi-empirical modified random pore model (MRPM) was the best-fitted model, indicating its suitability to CO2 gasification and confirming the catalytic influence of the inorganic matter in the studied samples. After demineralization, biomass chars presented higher values of activation energy and pre-exponential factor. According to the MRPM model, activation energy values within the range of 161.5–187.2 kJ mol−1 and 232.1–240.2 kJ mol−1, respectively, were obtained for the CO2 gasification of regular biochars and demineralized biochars. [ABSTRACT FROM AUTHOR]

Preservation of facial nerve function (FNF) during neurosurgery for cerebellopontine angle (CPA) tumors is paramount in elderly patients. Corticobulbar facial motor evoked potentials (FMEPs) allow assessment intraoperatively of the functional integrity of facial motor pathways, thus improving safety. We aimed to evaluate the significance of intraoperative FMEPs in patients 65 years and older. A retrospective cohort of 35 patients undergoing CPA tumors resection was reported; outcomes of patients aged 65–69 years vs. ≥70 years were compared. FMEPs were registered both from upper and lower face muscles, and amplitude ratios (minimum-to-baseline, MBR; final-to-baseline, FBR; and recovery value, FBR minus MBR) were calculated. Overall, 78.8% of patients had a good late (at 1 year) FNF, with no differences between age groups. In patients aged ≥70 years, MBR significantly correlated with late FNF. At receiver operating characteristics (ROC) analysis, in patients aged 65–69 years, FBR (with 50% cut-off value) could reliably predict late FNF. By contrast, in patients aged ≥70 years, the most accurate predictor of late FNF was MBR, with 12.5% cut-off. Thus, FMEPs are a valuable tool for improving safety in CPA surgery in elderly patients as well. Considering literature data, we noticed higher cut-off values for FBR and a role for MBR, which suggests an increased vulnerability of facial nerves in elderly patients compared to younger ones. [ABSTRACT FROM AUTHOR]