-
[show abstract]
[hide abstract]
ABSTRACT: This paper presents a novel method for inferring the odor based on neural activities observed from rats' main olfactory bulbs. Multi-channel extra-cellular single unit recordings were done by micro-wire electrodes (tungsten, 50μm, 32 channels) implanted in the mitral/tufted cell layers of the main olfactory bulb of anesthetized rats to obtain neural responses to various odors. Neural response as a key feature was measured by substraction of neural firing rate before stimulus from after. For odor inference, we have developed a decoding method based on the maximum likelihood (ML) estimation. The results have shown that the average decoding accuracy is about 100.0%, 96.0%, 84.0%, and 100.0% with four rats, respectively. This work has profound implications for a novel brain-machine interface system for odor inference.
Acoustics, Speech and Signal Processing (ICASSP), 2011 IEEE International Conference on; 06/2011 · 4.63 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The immunoreactivity and protein expression of olfactory marker protein (OMP) and tyrosine hydroxylase (TH) in the main olfactory bulb (MOB) of the dog during normal ageing was investigated. OMP immunolabelling was observed only in nerve bundles of the olfactory nerve (ONL) and glomerular layers (GL) and there was no OMP expression within cell bodies of any layer. TH immunolabelling was detected in all layers of the MOB except for the ONL. Most of the neurons expressing TH were distributed in the juxtaglomerular region and had a morphological appearance consistent with periglomerular, external tufted or superficial short axon cells. Dendrites of TH-immunoreactive neurons were closely apposed to OMP-immunoreactive nerve bundles within the glomeruli. There was no significant age-related loss of OMP and TH immunoreactivity and protein concentrations of these molecules were consistent in dogs of different ages. These results suggest that olfactory signal transduction to the GL via axons of olfactory receptor neurons remains unchanged during ageing in the dog.
Journal of comparative pathology 11/2009; 142(2-3):147-56. · 1.73 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In this research a mobile service robot with an i.MX21 embedded system and tele-operation server are developed. Because the robot system hands over complex jobs to the remote tele-operation server, we can make low cost and high performance mobile robot. A fuzzy control tele-operation algorithm for user face tracking and approaching is proposed and verified. With an i.MX21 embedded system and a tele-operation server, the developed mobile service robot can find human face and approach to robot users for 97% probability within 3m distance. The robot can provide various audio, visual and gesture services for education and entertainment in front of robot user. Remote robot users can utilize this robot for security service of audio and visual monitoring
SICE-ICASE, 2006. International Joint Conference; 11/2006
-
[show abstract]
[hide abstract]
ABSTRACT: In this paper we provide a quantitative electroencephalogram (EEG) analysis to study the effect of hypothermia on the neurological recovery of brain after cardiac arrest. We hypothesize that the brain injury results in a reduction in information of the brain rhythm. To measure the information content of the EEG a new measure called information quantity (IQ), which is the Shannon entropy of decorrelated EEG signals, is developed. For decorrelating EEG signals, we use the discrete wavelet transform (DWT) which is known to have good decorrelating properties and to show a good match to the standard clinical bands in EEG. In simulation for measuring the amount of information, the IQ shows better tracking capability for dynamic amplitude change and frequency component change than conventional entropy-based measures. Experiments are carried out in rodents to monitor the neurological recovery after cardiac arrest. In addition, EEG signal recovery under normothermic (37degC) and hypothermic (33degC) resuscitation following 5, 7 and 9 minutes of cardiac arrest is recorded and analyzed. Experimental results show that the IQ is higher for hypothermic than normothermic rats. The results quantitatively support the hypothesis that hypothermia accelerates the recovery of brain injury after cardiac arrest
Engineering in Medicine and Biology Society, 2006. EMBS '06. 28th Annual International Conference of the IEEE; 10/2006
-
Dong Jae Shin,
Y.C. Keh,
J.W. Kwon, E.H. Lee,
J.K. Lee,
M.K. Park,
J.W. Park,
Y.K. Oh,
S.W. Kim,
I.K. Yun, [......],
D. Heo,
J.S. Lee,
H.S. Shin,
H.S. Kim,
S.B. Park,
D.K. Jung,
Seongtaek Hwang,
Y.J. Oh,
D.H. Jang,
C.S. Shim
[show abstract]
[hide abstract]
ABSTRACT: This paper presents a low-cost bidirectional (BiDi) wavelength-division-multiplexed passive optical network (WDM-PON) employing colorless uncooled BiDi transceivers (TRxs) and superluminescent diode (SLD)-based broadband light sources (BLSs). The C band is allocated for upstream and the E+ band for downstream in consideration of BiDi packaging, SLD development, and wavelength alignment of dual-window arrayed waveguide gratings (AWGs). The BiDi TRx integrates an uncooled Fabry-Perot laser diode (FP-LD), a p-i-n photodiode (PD), and a 45°-angled thin-film filter in a small-form-factor (SFF) package. The SLD-based BLSs provide 13-dBm amplified spontaneous emissions (ASEs) with spectral ripples of < 3 dB and polarization dependencies of <1 dB. Colorless operations over 32 100-GHz-spaced channels are demonstrated from -20 to 80°C in 155-Mb/s BiDi transmissions over 25 km.
Journal of Lightwave Technology 02/2006; · 2.78 Impact Factor
-
D. Heo,
J.S. Lee,
I.K. Yun, H.C. Shin,
S.W. Kim,
D.K. Jung,
D.J. Shin,
H.S. Kim,
H.S. Shin,
S.B. Park,
S.T. Hwang,
Y.J. Oh,
Y.K. Oh,
D.H. Jang,
C.S. Shim
[show abstract]
[hide abstract]
ABSTRACT: We developed polarization-independent high-power superluminescent diodes (SLDs) for wavelength division multiplexed-passive optical network (WDM-PON) applications. The SLD presents CW output power of 150 mW, spectral bandwidth of 40 nm, polarization-dependent power variation of less than 1 dB, and spectral ripple of 3 dB at current of 1.47 A and temperature of 25 degC
Lasers and Electro-Optics Society, 2005. LEOS 2005. The 18th Annual Meeting of the IEEE; 11/2005
-
D J Shin,
Y.C. Keh,
J W Kwon,
E H Lee,
J K Lee,
M K Park,
J W Park,
J K Kang,
Y K Oh,
S W Kim, [......],
D. Heo,
J S Lee,
H S Shin,
H S Kim,
S B Park,
D.K. Jung,
Seongtaek Hwang,
Y J Oh,
D.H. Jang,
C S Shim
[show abstract]
[hide abstract]
ABSTRACT: We present a low-cost C/S-band WDM-PON employing colorless uncooled bidirectional transceivers and SOA-based broadband light sources. Colorless operations over 32 DWDM channels are demonstrated from -20 to 80°C in 155-Mb/s bidirectional transmissions over 25 km.
Optical Fiber Communication Conference, 2005. Technical Digest. OFC/NFOEC; 04/2005
-
[show abstract]
[hide abstract]
ABSTRACT: We present R-SOAs with improved modulation bandwidth of ∼1.35 GHz as WDM sources in 1.25 Gbit/s WDM-PONs. In back-to-back transmission using the R-SOA seeded by 0.6 nm-wide ASE of -20 dBm, receiver sensitivity at a 10<sup>-9 </sup>BER was - 25.3 dBm.
Lasers and Electro-Optics Society, 2004. LEOS 2004. The 17th Annual Meeting of the IEEE; 12/2004
-
[show abstract]
[hide abstract]
ABSTRACT: A process of making a new type of silicon depth-probe microelectrode array is described using a combination of plasma and wet etch. The plasma etch, which is done using a low temperature oxide (LTO) mask, enables probe thickness to be controlled over a range from 5 to 90 mu. Bending tests show that the probe's mechanical strength depends largely on shank thickness. More force can be applied to thicker shanks while thinner shanks are more flexible. One can then choose a thickness and corresponding mechanical strength using the process developed. The entire probe shaping process is performed only at low temperature, and thus is consistent with the standard CMOS fabrication. Using the probe in recording from rat's somatosensory cortex, we obtained four channel simultaneous recordings which showed clear independence among channels with a signal-to-noise ratio performance comparable with that obtained using other devices.
IEEE Transactions on Biomedical Engineering 09/2000; 47(8):1082-7. · 2.28 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Cellular and biochemical responses of the pectoral muscle to variation in seasonal activity were studied in the bat, Murina leucogaster ognevi. We collected bats in mid-hibernation (February), end-hibernation (April), and mid-summer (August) to track major activity periods in their annual cycle. Our findings indicated that myofiber cross-sectional area decreased to 68% between mid- and end-hibernation, but returned to the winter level in mid-summer. Total soluble protein and total RNA concentrations were not altered over these sampling periods. Oxidative potential gauged by citrate synthase activity increased 1.47-fold from mid- to end-hibernation and then remained at the similar level in mid-summer. Glycolytic potential gauged by lactate dehydrogenase activity changed little between mid- and end-hibernation but increased 1.42-fold in summer, compared with the winter level. Thus, the myofibers underwent disuse atrophy during hibernation, while enzymatic catalytic function recovered towards the level of mid-summer.
Comparative Biochemistry and Physiology - Part A Molecular & Integrative Physiology 07/2000; 126(2):245-50. · 2.23 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We investigated the effects of substance P (SP) on nitric oxide (NO) synthase activity in macrophages by measuring the production of nitrite and the expression of inducible NO synthase (iNOS) mRNA and protein. In LPS-activated macrophages, SP stimulated NO production in time and concentration dependent manners. These SP effects were blocked by a specific NK-1 receptor antagonist. Furthermore, SP stimulation increased the levels of both iNOS mRNA and iNOS protein. These results demonstrate that SP can increase LPS induced NO production in macrophages by augmenting the induction of iNOS expression. We also examined the role of SP on acute-cold stress induced altered production of NO by mouse peritoneal macrophages. SP enhanced the LPS-induced macrophages NO production from stressed mice relative to the non-stressed mice. These results suggest that SP may have an important modulatory role in production of NO by macrophages.
Immunopharmacology 05/1999; 41(3):219-26.
-
[show abstract]
[hide abstract]
ABSTRACT: Administration of the excitotoxin kainate produces seizure activity and selective neuronal death in various brain areas. We examined the degeneration pattern of hippocampal neurons following systemic injections of kainate in the hamster and the rat. As reported, treatment with kainate resulted in severe neuronal loss in the hilus and CA3 in the rat. While the hilar neurons were also highly vulnerable to kainate in the hamster, neurons in the CA1 area, but not CA3, were highly sensitive to kainate. In both animals, immunoreactivity to anti-p50 nuclear factor kappa B antibody was increased in nuclei of the hilar neurons within 4 h following administration of kainate. Kainate treatment also increased the nuclear factor kappa B immunoreactivity in hamster CA1 neurons and rat CA3 neurons 24 h later. Neurons showing intense nuclear factor kappa B signal were stained with acid fuchsin. Kainate also increased DNA binding activity of p50 and p65 nuclear factor kappa B in the nuclear extract of the hippocampal formation as analysed by electrophoretic mobility shift assay in the hamster, suggesting that activation of nuclear factor kappa B may contribute to kainate-induced hippocampal degeneration. Administration of 100 nmol dizocilpine maleate 3 h prior to kainate attenuated kainate-induced activation of nuclear factor kappa B and neuronal death in CA1 in the hamster. The present study provides evidence that the differential vulnerability of neurons in the rat and the hamster hippocampus to kainate is partly mediated by mechanisms involving N-methyl-D-aspartate-dependent activation of nuclear factor kappa B.
Neuroscience 01/1999; 94(1):83-91. · 3.38 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Activity-dependent changes of conduction velocity (CV) and conduction block in single A(delta) fibers of primary afferent neurons were characterized in a rat model of neuropathy (NP). Injured dorsal root (DR) fiber in NP rats exhibited profoundly greater decreases of CV following impulse activity than did DR fiber in normal rats. Activity-dependent conduction block was absent up to 100 Hz of activity rate in DR fiber of NP rats, but was present above 25 Hz in normal rats. Profiles of activity dependence in sciatic fibers were similar in both NP and normal rats. These results suggest that nerve injury may alter activity-dependent hypoexcitability of A(delta) DR fibers. Furthermore, this excitability change may be responsible for the elevated pain perception in neuropathy.
Neuroreport 11/1997; 8(15):3201-5. · 1.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The effects of topical application of interleukin-6 (IL-6) on the short and long latency evoked unit responses of the neurones in the primary somatosensory (SI) cortex were determined quantitatively in anaesthetized rats. IL-6 (0.01, 0.1, 1.0 units) significantly suppressed (-15.13 +/- 3.4%) short latency afferent sensory responses, while it induced profound facilitation (+464.74 +/- 132.7%) of long latency responses in a dose-dependent manner. IL-6-induced afferent modulations fully recovered by 60 min after drug administration. In control experiments, saline solution containing 0.2% bovine serum albumin, used as a vehicle, did not affect afferent sensory transmission. Implications of these results are discussed with reference to the different somatosensory functions of short and long latency response components in the SI cortex.
Neuroreport 10/1997; 8(13):2841-4. · 1.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Activity-dependent changes of the conduction latency of single A beta fibers of primary afferent neurons were characterized in both neuropathic (L4 and L6 ligated) and normal rats. Activity-dependent increases in conduction latency of dorsal root fibers in neuropathic rats were significantly stronger than those in normal rats. Different profiles of activity dependence were also observed between injured and adjacent intact dorsal root fibers of neuropathic rats. However, activity-dependent latency changes in sciatic nerves distal to the dorsal root ganglion were not different between neuropathic and normal rats. These results suggest that partial nerve injury induces activity-dependent excitability changes in the dorsal root fibers of neuropathic rat and that these changes may be responsible for the altered sensory processing such as those seen in allodynia.
Neuroreport 09/1997; 8(12):2813-6. · 1.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Single unit responses of the primary somatosensory (SI) cortical neurons to the stimulation of the forepaw single digit were monitored in anesthetized rats before and after subcutaneous injection of lidocaine to an ipsilateral homologous receptive field (IHRF). Quantitative determination of the temporal changes of afferent sensory transmission was done by analyzing poststimulus time histograms of unit responses. Temporary deafferentation to the IHRF induced immediate, but reversible suppression of afferent sensory transmission in the SI cortex and this suppression lasts up to 35 min post-deafferentation period (during 10-15 min, -21.81 +/- 5.9%, P < 0.01). This result suggests that temporary absence of afferent inflow from the digit to the SI cortex may exert interhemispheric modulation of afferent sensory transmission in the opposite somatosensory cortex of anesthetized rats.
Neuroscience Letters 07/1997; 230(2):137-9. · 2.11 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The effects of acute lowering of body temperature on afferent sensory transmission to the primary somatosensory cortex were determined quantitatively in anaesthetized rats and hamsters. Rats showed no change in afferent sensory transmission until 27 degrees C, but dramatic suppression between 26 degrees C and 22 degrees C, reaching 100% inhibition at 21 degrees C. Hamsters exhibited gradual suppression of sensory transmission from 34 degrees C to 18 degrees C, reaching 95% inhibition at 18 degrees C. Differential effects were also observed during rewarming up to 37 degrees C. Response latencies were also differentially affected during hypothermia in rats and hamsters. These results suggest the presence of inherently different neural mechanisms to process somatosensory information during transient lowering of body temperature between hibernators and non-hibernators.
Neuroreport 01/1997; 8(1):41-4. · 1.66 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The presence of somatostatin-like immunoreactive neurons was examined in the rabbit vestibular ganglion by using immunohistochemical techniques. About 22% (n = 153) of the total ganglion cells (n = 699) examined were somatostatin-immunoreactive and they were diffusely present throughout the ganglion. Majority of the somatostatin-immunoreactive cells were large (long diameter, 23-31 microns, 74%; short diameter, 20-25 microns, 76%) and they had oval or spherical cell bodies with well developed Nissl's body. However, about 78% (n = 546) of the total ganglion cells examined were not immunoreactive to the somatostatin. The presence of the somatostatin-immunoreactive neurons in the vestibular ganglion suggests a possibility that somatostatin may be involved in the modulation of afferent sensory transmission from the vestibular organ of the rabbit.
Neuroscience Letters 11/1996; 217(2-3):129-32. · 2.11 Impact Factor
-
M. Racanelli,
W.M. Huang, H.C. Shin,
J. Foerstner,
B.-Y. Hwang,
S. Cheng,
P.L. Fejes,
H. Park,
T. Wetteroth,
S. Hong,
H. Shin,
S.R. Wilson
[show abstract]
[hide abstract]
ABSTRACT: The impact of stress and dopant redistribution along the field
edge of SOI devices on offstate leakage, low voltage performance, and
yield is discussed. For the first time, stress caused by overoxidation
of the field region is shown to cause excessive device leakage and yield
loss. A modified PBL isolation scheme is used to minimize this effect.
Dopant redistribution is known to cause field edge leakage and is shown
to contribute to narrow channel effects. A novel integration scheme is
described to reduce the impact of dopant redistribution and result in a
TFSOI technology suitable for low power applications
Electron Devices Meeting, 1995., International; 01/1996
-
[show abstract]
[hide abstract]
ABSTRACT: Single unit recordings were made from the ventral posterior lateral thalamus of anaesthetized rats to characterize responses to the activation of new receptive fields induced by either local anaesthesia or amputation. Receptive fields confined to single digits were identified and evoked unit responses to the stimulation of single digits were quantitated before and after deafferentation. Although both methods of denervation rapidly induced similar new receptive fields from the adjacent single digit, they exhibited quite different temporal changes of the evoked unit responses from new receptive fields. This difference in the evoked unit responses from the new receptive fields may be related to either the different nature or the outcome of the two types of deafferentation.
Neuroreport 01/1996; 7(1):33-6. · 1.66 Impact Factor
