Background: The aim of the present study was to investigate if high amplitude high frequency oscillations(haHFOs) could be a biomarker of posttraumatic epileptogenesis. Methods: After an initial craniotomy of rats and...Background: The aim of the present study was to investigate if high amplitude high frequency oscillations(haHFOs) could be a biomarker of posttraumatic epileptogenesis. Methods: After an initial craniotomy of rats and inducement of traumatic brain injury(TBI) through a fluid percussion, recording microelectrodes were implanted bilaterally in different brain areas.Wideband brain electrical activity was recorded intermittently from Day 1 of TBI and continued till week 21. HaHFO analysis was performed during the first 4 weeks to investigate whether the occurrence of this brain activity predicted development of epilepsy or not. Results: Of the 21 rats which received the TBI, 9 became epileptic(E+) and 12 did not(E-). HaH FOs were observed in the prefrontal and perilesional cortices, hippocampus, and striatum in both E+ and E-group. In comparison to the rats in E-, the E+ group showed a significant increase in the rate of haHFO from weeks 1 to 4 after TBI.Conclusion: The results indicate that an increase in the rate of haHFOs after TBI could be an electroencephalographic biomarker of posttraumatic epileptogenesis.展开更多
In this paper, 0.15-μm gate-length In0.52Al0.48As/In0.53Ga0.47As InP-based high electron mobility transistors （HEMTs） each with a gate-width of 2×50 μm are designed and fabricated. Their excellent DC and RF c...In this paper, 0.15-μm gate-length In0.52Al0.48As/In0.53Ga0.47As InP-based high electron mobility transistors （HEMTs） each with a gate-width of 2×50 μm are designed and fabricated. Their excellent DC and RF characterizations are demonstrated. Their full channel currents and extrinsic maximum transconductance （gm,max） values are measured to be 681 mA/mm and 952 mS/mm, respectively. The off-state gate-to-drain breakdown voltage （BVGD） defined at a gate current of-1 mA/mm is 2.85 V. Additionally, a current-gain cut-off frequency （fT） of 164 GHz and a maximum oscillation frequency （fmax） of 390 GHz are successfully obtained; moreover, the fmax of our device is one of the highest values in the reported 0.15-μm gate-length lattice-matched InP-based HEMTs operating in a millimeter wave frequency range. The high gm,max, BVGD, fmax, and channel current collectively make this device a good candidate for high frequency power applications.展开更多
基金supported by research grants from the National Institutes of Health,USA。
文摘Background: The aim of the present study was to investigate if high amplitude high frequency oscillations(haHFOs) could be a biomarker of posttraumatic epileptogenesis. Methods: After an initial craniotomy of rats and inducement of traumatic brain injury(TBI) through a fluid percussion, recording microelectrodes were implanted bilaterally in different brain areas.Wideband brain electrical activity was recorded intermittently from Day 1 of TBI and continued till week 21. HaHFO analysis was performed during the first 4 weeks to investigate whether the occurrence of this brain activity predicted development of epilepsy or not. Results: Of the 21 rats which received the TBI, 9 became epileptic(E+) and 12 did not(E-). HaH FOs were observed in the prefrontal and perilesional cortices, hippocampus, and striatum in both E+ and E-group. In comparison to the rats in E-, the E+ group showed a significant increase in the rate of haHFO from weeks 1 to 4 after TBI.Conclusion: The results indicate that an increase in the rate of haHFOs after TBI could be an electroencephalographic biomarker of posttraumatic epileptogenesis.
基金Project supported by the National Basic Research Program of China(Grant Nos.2010CB327502 and 2010CB327505)the Advance Research Project(Grant No.5130803XXXX)
文摘In this paper, 0.15-μm gate-length In0.52Al0.48As/In0.53Ga0.47As InP-based high electron mobility transistors （HEMTs） each with a gate-width of 2×50 μm are designed and fabricated. Their excellent DC and RF characterizations are demonstrated. Their full channel currents and extrinsic maximum transconductance （gm,max） values are measured to be 681 mA/mm and 952 mS/mm, respectively. The off-state gate-to-drain breakdown voltage （BVGD） defined at a gate current of-1 mA/mm is 2.85 V. Additionally, a current-gain cut-off frequency （fT） of 164 GHz and a maximum oscillation frequency （fmax） of 390 GHz are successfully obtained; moreover, the fmax of our device is one of the highest values in the reported 0.15-μm gate-length lattice-matched InP-based HEMTs operating in a millimeter wave frequency range. The high gm,max, BVGD, fmax, and channel current collectively make this device a good candidate for high frequency power applications.
