Objective： The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment （MCI） w...Objective： The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment （MCI） was investigated. Methods：Subjects included 35 MCI patients according to the DSM-Ⅳ criteria （mean age： 62.3, SD： 6.5） and 34 healthy controls （mean age：57.4, SD： 4.0） were selected from the community at large. All subjects performed a simple calculation and recall task with three levels of working memory load while electroencephalograph （EEG） signal was recorded. The spectral EEG power was computed over alphal （8.0～10.0 Hz） and alpha2 （10.5～13.0 Hz） frequency bands and was compared between rest stage and working memory processing stage by two-way ANOVA. Post hoc testing analyzed the differences between each two levels of working memory load during task processing. The inter-hemisphere EEG coherence of frontal （F3-F4）, central （C3-C4）, parietal （P3-P4）, temporal （T5-T6） as well as occipital （O1-O2） was compared between MCI patients and normal controls. The EEG signals from F3-C3,F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs resulted from the intra-hemispheric action for alphal and alpha2 frequency bands. Result： There was significantly higher EEG power from MCI patients than from normal controls both at rest and during working memory processing. Significant differences existed between rest condition and three-level working memory tasks （P〈0.001）. The inter- and intra-hemispheric coherence during working memory tasks showed a ＂drop to rise＂ tendency compared to that at rest condition. There was significantly higher coherence in MCI patients than in the controls.When task difficulties increased, the cortical connectivity of intra-hemispheric diminished while the inter-hemispheric connectivity dominantly maintained the cognitive processing in MCI patients. Conclusion： The results of the present study indicate that the alpha frequency band may be the characteristic band in distinguishing MCI patients from normal controls during working memory tasks. MCI patients exhibit greater inter-hemispheric connectivity than intra-hemispheric connectivity when memory demands increase. MCI patients mobilize a compensatory mechanism to maintain the processing effectiveness while the processing efficiency is reduced.展开更多
According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rec...According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rectangle microstrip applicator in microwave hyperthermia. Results of the extensive simulations and experiments show that the introduction of the lens to the clinical used antenna can significantly improve the directivity and hence increase the microwave power density in near field. In microwave hyperthermia applications, the lens antenna will exhibit superior directivity, high gain and well thermal efficiency for tumor in superficial layer. Besides, it has small treatment area that is helpful for reducing the injury of the normal tissue around the tumor.展开更多
OBJECTIVE:To investigate the effects of different frequencies of electro-acupuncture at Shuigou(GV 26) on the latent period and wave amplitude of motor evoked potentials(MEPs) in rats with focal cerebral infarction.ME...OBJECTIVE:To investigate the effects of different frequencies of electro-acupuncture at Shuigou(GV 26) on the latent period and wave amplitude of motor evoked potentials(MEPs) in rats with focal cerebral infarction.METHODS:Fifty healthy male Wistar rats were randomly divided into five groups:controls,model,2 Hz Shuigou,50 Hz Shuigou and 100 Hz Shuigou.There were 10 rats in each group.Using a modification of a technique for middle cerebral artery occlusion,focal cerebral ischemic injury was induced in all rats except those in the control group.The rats in the control group received no treatment.After behavioral deficit had been evaluated using the Zausinger 6-point neurological function score,therats in the Shuigou groups underwent acupuncture and continuous wave stimulation at a frequency of 2 Hz,50 Hz or 100 Hz(intensity 1 mA) for 10 min twice daily for 3 days.The control and model groups underwent no intervention.Zausinger 6-point neurological function score and MEPs were measured 72 h after the start of treatment.RESULTS:The neurological function scores of the three Shuigou groups were significantly higher than those of the model group(P<0.05).There was no significant difference between sides in the latency and amplitude of MEPs in the model group(P> 0.05).The latency on the affected side in the model group was significantly longer than that in the control group(P<0.05) and the amplitude on affected side was significantly reduced(P<0.01).After 3 days of electro-acupuncture,the latency on the affected side in the 2 Hz Shuigou group was significantly shortened(P<0.05) and the amplitude was significantly increased(P<0.05) compared with the model group.CONCLUSION:Low frequency electro-acupuncture at Shuigou(GV 26) can promote recovery of motor function after focal cerebral ischemic injury in rats.展开更多
Sputtering deposition coatings offer significant advantages on electron beam (EB) deposition, including high packing density, environmental stability and extremely low losses. But the inherent high compressive stress ...Sputtering deposition coatings offer significant advantages on electron beam (EB) deposition, including high packing density, environmental stability and extremely low losses. But the inherent high compressive stress affects its application in high power laser system. This paper describes the technical feasibility of high damage threshold laser mirrors deposited by a novel remote plasma sputtering technique. This technique is based on generating intensive plasma remotely from the target and then magnetically steering the plasma to the target to realize the full uniform sputtering. The pseudo-independence between target voltage and target current provides us very flexible parameters tuning, especially for the films stress control. Deposition conditions are optimized to yield fully oxidized and low compressive stress single layer HfO2 and SiO2. The high damage threshold of 43.8 J/cm2 for HfO2/ SiO2 laser mirrors at 1064 nm is obtained. For the first time the remote plasma sputtering is successfully applied in depositing laser mirrors with high performance.展开更多
基金Project (No.2003B070) supported by the Science and TechnologyProgram of Zhejiang Province, China
文摘Objective： The functional relationship between calculated alpha band spectral power and inter-/intra-hemispheric coherence during a three-level working memory task of patients with mild cognitive impairment （MCI） was investigated. Methods：Subjects included 35 MCI patients according to the DSM-Ⅳ criteria （mean age： 62.3, SD： 6.5） and 34 healthy controls （mean age：57.4, SD： 4.0） were selected from the community at large. All subjects performed a simple calculation and recall task with three levels of working memory load while electroencephalograph （EEG） signal was recorded. The spectral EEG power was computed over alphal （8.0～10.0 Hz） and alpha2 （10.5～13.0 Hz） frequency bands and was compared between rest stage and working memory processing stage by two-way ANOVA. Post hoc testing analyzed the differences between each two levels of working memory load during task processing. The inter-hemisphere EEG coherence of frontal （F3-F4）, central （C3-C4）, parietal （P3-P4）, temporal （T5-T6） as well as occipital （O1-O2） was compared between MCI patients and normal controls. The EEG signals from F3-C3,F4-C4, C3-P3, C4-P4, P3-O1, P4-O2, T5-C3, T6-C4, T5-P3 and T6-P4 electrode pairs resulted from the intra-hemispheric action for alphal and alpha2 frequency bands. Result： There was significantly higher EEG power from MCI patients than from normal controls both at rest and during working memory processing. Significant differences existed between rest condition and three-level working memory tasks （P〈0.001）. The inter- and intra-hemispheric coherence during working memory tasks showed a ＂drop to rise＂ tendency compared to that at rest condition. There was significantly higher coherence in MCI patients than in the controls.When task difficulties increased, the cortical connectivity of intra-hemispheric diminished while the inter-hemispheric connectivity dominantly maintained the cognitive processing in MCI patients. Conclusion： The results of the present study indicate that the alpha frequency band may be the characteristic band in distinguishing MCI patients from normal controls during working memory tasks. MCI patients exhibit greater inter-hemispheric connectivity than intra-hemispheric connectivity when memory demands increase. MCI patients mobilize a compensatory mechanism to maintain the processing effectiveness while the processing efficiency is reduced.
文摘According to the aplanatism theory, lens can be used to focus the electromagnetic wave. A piano-convex hyperboloid of revo- lution lens made of low loss material is designed for combinatorial applications with the rectangle microstrip applicator in microwave hyperthermia. Results of the extensive simulations and experiments show that the introduction of the lens to the clinical used antenna can significantly improve the directivity and hence increase the microwave power density in near field. In microwave hyperthermia applications, the lens antenna will exhibit superior directivity, high gain and well thermal efficiency for tumor in superficial layer. Besides, it has small treatment area that is helpful for reducing the injury of the normal tissue around the tumor.
基金Supported by National Natural Science Foundation of China (No.30873304)
文摘OBJECTIVE:To investigate the effects of different frequencies of electro-acupuncture at Shuigou(GV 26) on the latent period and wave amplitude of motor evoked potentials(MEPs) in rats with focal cerebral infarction.METHODS:Fifty healthy male Wistar rats were randomly divided into five groups:controls,model,2 Hz Shuigou,50 Hz Shuigou and 100 Hz Shuigou.There were 10 rats in each group.Using a modification of a technique for middle cerebral artery occlusion,focal cerebral ischemic injury was induced in all rats except those in the control group.The rats in the control group received no treatment.After behavioral deficit had been evaluated using the Zausinger 6-point neurological function score,therats in the Shuigou groups underwent acupuncture and continuous wave stimulation at a frequency of 2 Hz,50 Hz or 100 Hz(intensity 1 mA) for 10 min twice daily for 3 days.The control and model groups underwent no intervention.Zausinger 6-point neurological function score and MEPs were measured 72 h after the start of treatment.RESULTS:The neurological function scores of the three Shuigou groups were significantly higher than those of the model group(P<0.05).There was no significant difference between sides in the latency and amplitude of MEPs in the model group(P> 0.05).The latency on the affected side in the model group was significantly longer than that in the control group(P<0.05) and the amplitude on affected side was significantly reduced(P<0.01).After 3 days of electro-acupuncture,the latency on the affected side in the 2 Hz Shuigou group was significantly shortened(P<0.05) and the amplitude was significantly increased(P<0.05) compared with the model group.CONCLUSION:Low frequency electro-acupuncture at Shuigou(GV 26) can promote recovery of motor function after focal cerebral ischemic injury in rats.
基金supported by the National Natural Science Foundation of China (No. 50802080)the Natural Science Foundation of Fujian Province of China (No.2010Jo1349)
文摘Sputtering deposition coatings offer significant advantages on electron beam (EB) deposition, including high packing density, environmental stability and extremely low losses. But the inherent high compressive stress affects its application in high power laser system. This paper describes the technical feasibility of high damage threshold laser mirrors deposited by a novel remote plasma sputtering technique. This technique is based on generating intensive plasma remotely from the target and then magnetically steering the plasma to the target to realize the full uniform sputtering. The pseudo-independence between target voltage and target current provides us very flexible parameters tuning, especially for the films stress control. Deposition conditions are optimized to yield fully oxidized and low compressive stress single layer HfO2 and SiO2. The high damage threshold of 43.8 J/cm2 for HfO2/ SiO2 laser mirrors at 1064 nm is obtained. For the first time the remote plasma sputtering is successfully applied in depositing laser mirrors with high performance.
