http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Sven Möllers (검색결과 2 건)
- 무료
- 기관 내 무료
- 유료
-
Haktan Altinova,Sven Möllers,Ronald Deumens,Jose Gerardo-Nava,Tobias Führmann,Sabien Geraldine Antonia van Neerven,Ahmet Bozkurt,Christian Andreas Mueller,Hans Joachim Hoff,Ingo Heschel,Joachim Weis,G 한국조직공학과 재생의학회 2016 조직공학과 재생의학 Vol.13 No.5
The implantation of bioengineered scaffolds into lesion-induced gaps of the spinal cord is a promising strategy for promoting functional tissue repair because it can be combined with other intervention strategies. Our previous investigations showed that functional improvement following the implantation of a longitudinally microstructured collagen scaffold into unilateral mid-cervical spinal cord resection injuries of adult Lewis rats was associated with only poor axon regeneration within the scaffold. In an attempt to improve graft-host integration as well as functional recovery, scaffolds were seeded with highly enriched populations of syngeneic, olfactory bulb-derived ensheathing cells (OECs) prior to implantation into the same lesion model. Regenerating neurofilament-positive axons closely followed the trajectory of the donor OECs, as well as that of the migrating host cells within the scaffold. However, there was only a trend for increased numbers of regenerating axons above that supported by non-seeded scaffolds or in the untreated lesions. Nonetheless, significant functional recovery in skilled forelimb motor function was observed following the implantation of both seeded and non-seeded scaffolds which could not be correlated to the extent of axon regeneration within the scaffold. Mechanisms other than simple bridging of axon regeneration across the lesion must be responsible for the improved motor function.
-
Effect of higher frequency on the classification of steady-state visual evoked potentials
Won, Dong-Ok,Hwang, Han-Jeong,Dä,hne, Sven,Mü,ller, Klaus-Robert,Lee, Seong-Whan IOP 2016 Journal of neural engineering Vol.13 No.1
<P> <I>Objective.</I> Most existing brain–computer interface (BCI) designs based on steady-state visual evoked potentials (SSVEPs) primarily use low frequency visual stimuli (e.g., <20 Hz) to elicit relatively high SSVEP amplitudes. While low frequency stimuli could evoke photosensitivity-based epileptic seizures, high frequency stimuli generally show less visual fatigue and no stimulus-related seizures. The fundamental objective of this study was to investigate the effect of stimulation frequency and duty-cycle on the usability of an SSVEP-based BCI system. <I>Approach.</I> We developed an SSVEP-based BCI speller using multiple LEDs flickering with low frequencies (6–14.9 Hz) with a duty-cycle of 50%, or higher frequencies (26–34.7 Hz) with duty-cycles of 50%, 60%, and 70%. The four different experimental conditions were tested with 26 subjects in order to investigate the impact of stimulation frequency and duty-cycle on performance and visual fatigue, and evaluated with a questionnaire survey. Resting state alpha powers were utilized to interpret our results from the neurophysiological point of view. <I>Main results.</I> The stimulation method employing higher frequencies not only showed less visual fatigue, but it also showed higher and more stable classification performance compared to that employing relatively lower frequencies. Different duty-cycles in the higher frequency stimulation conditions did not significantly affect visual fatigue, but a duty-cycle of 50% was a better choice with respect to performance. The performance of the higher frequency stimulation method was also less susceptible to resting state alpha powers, while that of the lower frequency stimulation method was negatively correlated with alpha powers. <I>Significance.</I> These results suggest that the use of higher frequency visual stimuli is more beneficial for performance improvement and stability as time passes when developing practical SSVEP-based BCI applications.</P>
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
