抗宇宙射线的高压IGBT模块的优化设计

高压功率半导体器件在高压条件下工作时会出现由宇宙射线辐射引起的失效[1-3],该现象在1994年被第一次描述,现已得到证实。这种现象被称为单离子烧毁(SEB),属永久性失效。IGBT电压范围已逐渐升高到6.5kV,将不可避免地遇到由宇宙射线引起的失效问题。考虑在宇宙射线下的长期直流电压稳定性(LongTerm DC volt-age Stability,简称LTDS)已成为高压IGBT(HVIGBT)的设计重点。本文介绍了一种既能提高LTDS性能、又不牺牲电学特性的6.5kV高压HVIGBT模块的设计方法,同时报告了加速中子辐照实验的验证和分析结果。

Neck neuromuscular treatment for depressive disorders with cervical muscular tension or chronic neck pain—A pilot study

BACKGROUND: An intimate relationship between depressive disorders and chronic pain is well known but often neglected. We studied patients with depressive disorders accompanying cervical muscular tension or neck pain. They also complaints of various physical, psychosomatic, and psychiatric signs such as anxiety and non-specific complaints related to autonomic imbalance. These complaints or symptoms are commonly resistant to pharmacological treatment, and thus we tried to treat these conditions by reducing their cervical muscular tension or pain. METHODS: We evaluated 30 complaints of 138 patients suffering from depressive disorders with cervical muscular abnormality (52 men and 86 women). The presence of the 30 complaints was evaluated as ‘positive’ or ‘negative’ before and during treatment. The necks of all patients were treated using low-frequency stimulation, micro-wave therapies, electric needle application, and acupuncture. RESULTS: Reducing cervical muscular tension remitted or cured the 30 complaints including depressive mood. The reduction of cervical muscle pain or tension initially ameliorated the depressive symptoms and anxiety, and subsequently improved their autonomic imbalances. Discriminant analysis of the first and second examinations correctly classified 95.3% of original grouped cases. CONCLUSION: Reducing cervical muscular tension is an effective treatment for patients suffering from depressive disorders with cervical neuromuscular pain or rigidity.

Females with schizophrenia have abnormal functional cortical connectivity in the gamma frequency during an auditory oddball task using magnetoencephalography

We studied differences in imaginary coherence (IC) of the gamma band between brain regions of female schizophrenia patients during the auditory oddball task using magnetoencephalography (MEG). Subjects were 12 right-handed female schizophrenia patients, who were evaluated by the Positive and Negative Syndrome Scales (PANSS). Functional connectivity during an auditory oddball task was reconstructed in low gamma (30 - 50 Hz) and high gamma (50 - 100 Hz and 100 - 150 Hz) bands, and represented by IC using seeds determined by the significant oscillatory power changes obtained by event-related synchronization (ERS) and event-related desynchronization (ERD) power measurements. Gamma ERS (30 - 50 Hz) power was decreased in the left precuneus at 500 - 750 ms and in the right precuneus at 750 - 1000 ms. IC in the gamma band (50 - 100 Hz) was decreased between the right precuneus (seed) and right paracentral lobule (target) and between the right precuneus and right hypothalamus at 0 - 250 ms. IC in the gamma band (100 - 150 Hz) was increased between the left precuneus and right cuneus (Brodmann area 7) at 250 - 500 ms, between the left precuneus and right culmen at 500 - 750 ms, and between the left precuneus and right cuneus (Brodmann area 17), between the left precuneus and right posterior cingulate cortex, and between the left precuneus and right caudate nucleus at 750 - 1000 ms. In the high gamma band (50 - 100 Hz) at 0 - 250 ms, significant positive correlations were shown between IC and conceptual disorganization in PANSS scores, between IC and unusual thought content score, and between IC and positive scale score. IC within the high gamma band in female schizophrenia patients showed two types of functional disconnection, intrahemispheric and interhemispheric. IC between the right or left precuneus and other specific cortical areas showed dysfunction, suggesting that the parietal lobe plays an important role in dysfunction in connectivity in the gamma band during the oddball task.

Subclinical synovitis detected by magnetic resonance imaging and ultrasonography following clinical remission in patients with rheumatoid arthritis:A retrospective study

Background:Subjective residual symptoms persist after clinical remission of rheumatoid arthritis(RA)in Japanese patients.Few studies have examined the relationship between these symptoms and subclinical inflammation using high-sensitivity imaging(musculoskeletal ultrasound[MSUS]and magnetic resonance imaging[MRI]).We examined the relationship between subjective residual symptoms and imaging findings in patients with RA who achieved clinical remission.Methods:We enrolled 30 patients with RA.The primary endpoint was the patients'subjective residual symptoms.The secondary endpoint was the relationship between the aforementioned symptoms and imaging findings.Results:Despite a mean Simplified Disease Activity Index of 1.3,imaging evaluation revealed inflammatory findings.In the multivariate analysis,the Health Assessment Questionnaire Disability Index(HAQ-DI)and pain visual analog scale(VAS)scores were extracted as independent related factors of subjective residual symptoms.The stratified analysis according to HAQ-DI showed a significant difference in synovitis on MRI between patients with and without residual disability(12.0±8.7 vs.5.3±5.3,respectively;p=0.0192).However,MSUS scores showed no significant difference in these two groups.In addition,no significant differences were found in MSUS and MRI scores between patients with and without residual pain VAS.Conclusions:Our findings demonstrated residual synovitis related to patientreported outcomes in patients with RA who achieved clinical remission.In particular,patients with an HAQ-DI score of>0.25 even after achieving clinical remission should be further examined by MRI and/or MSUS for the evaluation of residual synovitis.