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Infiltrative non-GBM gliomas are common primary intracranial malignancies, and postoperative adjuvant radiotherapy is recommended for most adult patients diagnosed with this disease to enhance local control and prolong intracranial progression-free survival (PFS). However, RT-related neurocognitive function (NCF) consequences should not be ignored. Early neurocognitive decline principally includes episodic memory, associated significantly with functions of the hippocampus. This prospective study aims to investigate the impact of adjuvant brain irradiation on neurocognitive performances and relevant oncological outcomes. Twenty-five patients with intracranial infiltrative non-GBM gliomas were enrolled when postoperative adjuvant RT was recommended. All recruited patients should receive baseline brain magnetic resonance imaging, and neuropsychological assessments before and 4 months after the RT course. A battery of neuropsychological measures, mainly including executive functions, memory, psychomotor speed and visuoconstructive ability, was used to evaluate NCFs of interest. Analyzing the delta values between post-irradiation and baseline NCF scores, we observed a robust trend reflecting cognitive stabilization rather than deterioration in almost all NCF. Both verbal and visual memory functions exhibited significant differences in the corresponding scaled scores (Z = −2.722, p =.006, regarding verbal memory; Z = −2.246, p =.025, concerning non-verbal memory). Moreover, patients' neuropsychological performances associated with psychomotor speed and executive functions also disclosed a tendency toward stabilization/improvement. This prospective study demonstrated that patients with infiltrative non-GBM exhibited a marked tendency toward neurocognitive stabilization after receiving postoperative adjuvant RT. Clinical trial registration: Trial Registration with ClinicalTrials.gov identifier: NCT03534050 [ABSTRACT FROM AUTHOR]

The radio frequency (RF) power and noise temperature dependency of buffer-free layer AlGaN/GaN on the 6 in. SiC substrate high electron mobility transistor were studied. The buffer-free structure has improved 3% characteristics of the current collapse and pulse measurement at a 30 V drain quiescent voltage. Compared with the conventional thick buffer layer (1.5–2 μm) structure design, the buffer-free layer with high structural quality AlN nucleation layers can reduce self-heating and thermal boundary resistance effect when the devices operate at a high DC power. The buffer-free device exhibits lower surface temperatures and higher powers at the same VGS and VDS than the standard device in thermal imaging measurements. In addition, traditional iron- or carbon-doped buffers were avoided in this design; thus, the buffer-induced microwave noise and thermal noise can be improved simultaneously. Without Fe- or C-doped buffer-induced trap behavior, the buffer-free structure improves the device DC characteristics and reduces the current collapse effect from the conventional buffer; thus, the device shows better linearity, noise figure, and RF small-signal characteristics. [ABSTRACT FROM AUTHOR]

Conventional treatment for treating primary central nervous system lymphoma (PCNSL) has consisted of either whole-brain radiotherapy (WBRT) or methotrexate (MTX)-based combined modality therapy. However, delayed cognitive sequelae have emerged as a significant debilitating complication in PCNSL patients. A prospective observational case-series study with prospective assessments of neurocognitive functions (NCFs), neuroimaging, and activities of daily living in newly-diagnosed PCNSL patients was undertaken. A battery of neuropsychological measures, used to evaluate NCFs, is composed of ten standardized NCF tests, representing four domains sensitive to disease and treatment effects (executive function, attention, verbal memory, psychomotor speed), and activities of daily living. A total of 15 patients with newly-diagnosed PCNSL were consecutively enrolled in this study. Comparing the NCF scores between the baseline (before WBRT) and post-treatment (after combined chemoradiation therapy) intervals (Mean = 122.33 days, SD = 34.49, range = 77-196), neurobehavioral outcomes consistently remained improving or stable in almost each domain of NCF. Specifically, the scores on Paced Auditory Serial Addition Test-Revised (PASAT-R) were significantly improved between the baseline and post-chemoradiation assessment. Under the multidisciplinary treatment guidelines for treating patients with newly-diagnosed PCNSL, multi-domain NCF become stabilized and even improved after the course of conformal WBRT combined with or without MTX-based chemotherapy. [ABSTRACT FROM AUTHOR]

Background: Whole brain radiotherapy (WBRT) has been the treatment of choice for patients with brain metastases. However, change/decline of neurocognitive functions (NCFs) resulting from impaired hippocampal neurogenesis might occur after WBRT. It is reported that conformal hippocampal sparing would provide the preservation of NCFs. Our study aims to investigate the hippocampal dosimetry and to demonstrate the correlation between hippocampal dosimetry and neurocognitive outcomes in patients receiving hippocampal sparing during WBRT (HS-WBRT).Methods: Forty prospectively recruited cancer patients underwent HS-WBRT for therapeutic or prophylactic purposes. Before receiving HS-WBRT, all participants received a battery of baseline neurocognitive assessment, including memory, executive functions and psychomotor speed. The follow-up neurocognitive assessment at 4 months after HS-WBRT was also performed. For the delivery of HS-WBRT, Volumetric Modulated Arc Therapy (VMAT) with two full arcs and two non-coplanar partial arcs was employed. For each treatment planning, dose volume histograms were generated for left hippocampus, right hippocampus, and the composite hippocampal structure respectively. Biologically equivalent doses in 2-Gy fractions (EQD2) assuming an alpha/beta ratio of 2 Gy were computed. To perform analyses addressing the correlation between hippocampal dosimetry and the change in scores of NCFs, pre- and post-HS-WBRT neurocognitive assessments were available in 24 patients in this study.Results: Scores of NCFs were quite stable before and after HS-WBRT in terms of hippocampus-dependent memory. Regarding verbal memory, the corresponding EQD2 values of 0, 10, 50, 80 % irradiating the composite hippocampal structure with <12.60 Gy, <8.81, <7.45 Gy and <5.83 Gy respectively were significantly associated with neurocognitive preservation indicated by the immediate recall of Word List Test of Wechsler Memory Scale-III. According to logistic regression analyses, it was noted that dosimetric parameters specific to left sided hippocampus exerted an influence on immediate recall of verbal memory (adjusted odds ratio, 4.08; p-value, 0.042, predicting patients' neurocognitive decline after receiving HS-WBRT).Conclusions: Functional preservation by hippocampal sparing during WBRT is indeed achieved in our study. Providing that modern VMAT techniques can reduce the dose irradiating bilateral hippocampi below dosimetric threshold, patients should be recruited in prospective trials of hippocampal sparing during cranial irradiation to accomplish neurocognitive preservation while maintaining intracranial control.Trial Registration: Current Controlled Trials NCT02504788. [ABSTRACT FROM AUTHOR]

A metal–insulator–semiconductor p-type GaN gate high-electron-mobility transistor (MIS-HEMT) with an Al2O3/AlN gate insulator layer deposited through atomic layer deposition was investigated. A favorable interface was observed between the selected insulator, atomic layer deposition–grown AlN, and GaN. A conventional p-type enhancement-mode GaN device without an Al2O3/AlN layer, known as a Schottky gate (SG) p-GaN HEMT, was also fabricated for comparison. Because of the presence of the Al2O3/AlN layer, the gate leakage and threshold voltage of the MIS-HEMT improved more than those of the SG-HEMT did. Additionally, a high turn-on voltage was obtained. The MIS-HEMT was shown to be reliable with a long lifetime. Hence, growing a high-quality Al2O3/AlN layer in an HEMT can help realize a high-performance enhancement-mode transistor with high stability, a large gate swing region, and high reliability. [ABSTRACT FROM AUTHOR]

Fixed‐width Booth multiplier (FWBM) plays a significant role in the arouse of approximate computing (AC) field. In this paper, a row‐based binary‐weighted compensator (RBC) for fixed‐width Booth multiplication is proposed. The derived binary‐weighted close‐form minimizes the conversion loss and hardware cost. With the proposed close‐form, the partial product array can be reduced dramatically. Consequently, the compact FWBM with the proposed RBC not only shortens the critical path to at least 24% but also minimizes the power dissipation to at least 44%. Moreover, the proposed RBC outperforms the state‐of‐art with a maximum merit improvement of 39%. By implementing the proposed RBC‐FWBM in the FIR filter, we manage to demonstrate the practicality of the proposed design with a significant reduction in power‐dissipation and delay while maintaining high accuracy. [ABSTRACT FROM AUTHOR]

Background: Whole brain radiotherapy (WBRT) is the treatment of choice for patients with brain metastases. However, neurocognitive functions (NCFs) decline due to impaired hippocampal neurogenesis might occur thereafter. It is hypothesized that conformal hippocampal avoidance during the course of WBRT (HA-WBRT) might provide meaningful NCF preservation. Our study aims to demonstrate the impact of delivering HA-WBRT on NCF changes in patients receiving WBRT., Methods: Twenty-five patients who were referred for prophylactic cranial irradiation (PCI) or treating oligometastatic brain disease were enrolled in the study. Before the HA-WBRT course, all participants should receive baseline neurocognitive assessment, including memory, executive functions, and psychomotor speed. The primary endpoint was delayed recall, as determined by the change/decline in verbal memory [Wechsler Memory Scale - 3rd edition (WMS III)- Word List score] from the baseline assessment to 4 months after the start of HA-WBRT., Results: Only three patients belonged to the clinical setting of PCI; the remaining 22 patients had oligometastatic brain disease. Regarding neurocognitive outcomes, no statistically significant differences were found between various NCF scores obtained at baseline and at post-radiotherapy intervals, in immediate verbal memory and non-verbal memory, except for delayed recall memory on Word List (F = 5.727, p = 0.048)., Conclusions: Functional preservation by hippocampal sparing during WBRT could largely be achieved in this study, which also suggests that HA-WBRT should be a feasible technique preserving neurocognitive functions while maintaining intracranial control.