• Title/Summary/Keyword: Number of neurons

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Neuronal activity in the periaqueductal gray associated with chronic cannula implantation and microdialysis (Chronic cannula implantation 및 microdialysis가 periaqueductal gray내 신경세포 활성에 미치는 영향)

  • Lee, Jang-hern;Han, Ho-jae;Yang, Il-suk
    • Korean Journal of Veterinary Research
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    • v.38 no.4
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    • pp.720-729
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    • 1998
  • Immunohistochemical technique of the c-fos primary gene protein, Fos, was used to analyze the effects of external factors on the neuronal activities in the periaqueductal gray(PAG) of the intact rats, sham-operated rats and post-operated stress control rats. In addition, the number of Fos positive neurons has been evaluated to verify the effects of cannula implantation and veratridine treatment on the neuronal activities in PAG area. The results were summerized as follow : 1. There was no significant difference in the number of Fos positive neurons observed in the caudal and middle portion of lateroventral PAG from cannula implanted rats and sham operated rats. 2. The number of Fos positive neurons in the PAG was not changed by the stress induced by connection of collecting tube to rats for 12 hours as compared to that of intact rats. 3. In the saline treated group, the Fos immunoreactivity in the PAG did not changed at 30 minutes and 1 hour after saline treatment as compared to that of intact rats. However, the number of Fos positive neurons was significantly increased at 2 hours after treatment compared to that of saline treated rats at 30 minutes after treatment. 4. The Fos immunoreactivity was dramatically increased at 30 minutes, 1 hour and 2 hours after veratridine treatment as compared to those of saline treated groups. The number of Fos immunoreative neurons showed the maximal level at 2 hours after veratridine treatment. 5. The Fos positive neurons induced by saline and veratridine treatment were mainly distributed in front of the microdialysis window. These results suggest that new microdialysis demonstrated in this study improves efficiency and accuracy to confine the neuronal activity in front of microdialysis window site. Moreover, this directional specificity allows us to locate probe tips adjacent to the brain area of the interest site rather than centering the probes within that brain area. Finally, This microdialysis method can be used to dialyse the neurotransmitters using concious and freely moving rats.

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A Study on NADPH-Diaphorase and Neuropeptide Y-Positive Neurons in The Brain Stem of Aged Rats (노화된 흰쥐의 뇌줄기에 분포하는 NADPH-Diaphorase 및 Neuropeptide Y양성 신경세포에 관한 연구)

  • Kim, Soon-Hee;Chang, Hwan-Il;Huh, Young-Buhm;Ahn, Hee-Kyung
    • Korean Journal of Biological Psychiatry
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    • v.3 no.2
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    • pp.191-202
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    • 1996
  • This study was aimed to charily the change of NADPH-diaphorase(NADPH-d) and neuropeptide Y(NPY) associated with aging of the rots. To verily the effect of aging of NPY and NADPH-d-positive neurons in the brain stem, the neurons were stained by the immunohistochemical and histochemical method. In the aged group, the number of NADPH-d-positive neurons was significantly decreased in substantia nigra lateralis, supragenual nucleus, raphe magnus nucleus and raphe obscurus nucleus as compared with control group. The number of NADPH-d-positive neurons was not significantly decreased in superior colliculus, interpeduncular nucleus, central gray. dorsal raphe nucleus, retrorubral nucleus, pedunculopontine tegmental nucleus, laterodorsal tegmental nucleus, pontine reticular nucleus, prepositus hypoglossal nucleus and nucleus solitarius of the aged rats. The NADPH-d and NPY-positive neurons were found in the interpeduncular nucleus, central gray, substantia nigra lateralis, laterodorsal tegmental nucleus, nucleus solitarius, raphe magnus nucleus, raphe obscurus nucleus of the control and aged groups. The coexistence of NADPH-d and NPY in the some cell was not found in the brain stem of both groups.

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Optimal Algorithm and Number of Neurons in Deep Learning (딥러닝 학습에서 최적의 알고리즘과 뉴론수 탐색)

  • Jang, Ha-Young;You, Eun-Kyung;Kim, Hyeock-Jin
    • Journal of Digital Convergence
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    • v.20 no.4
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    • pp.389-396
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    • 2022
  • Deep Learning is based on a perceptron, and is currently being used in various fields such as image recognition, voice recognition, object detection, and drug development. Accordingly, a variety of learning algorithms have been proposed, and the number of neurons constituting a neural network varies greatly among researchers. This study analyzed the learning characteristics according to the number of neurons of the currently used SGD, momentum methods, AdaGrad, RMSProp, and Adam methods. To this end, a neural network was constructed with one input layer, three hidden layers, and one output layer. ReLU was applied to the activation function, cross entropy error (CEE) was applied to the loss function, and MNIST was used for the experimental dataset. As a result, it was concluded that the number of neurons 100-300, the algorithm Adam, and the number of learning (iteraction) 200 would be the most efficient in deep learning learning. This study will provide implications for the algorithm to be developed and the reference value of the number of neurons given new learning data in the future.

The Effects of Sunghyangjunggi-san and Gwackhyangjunggi-san Extracts on Cerebral Ischemia Following the MCA Occlusion in Rat (흰쥐의 중대뇌동맥 결찰로 유발된 뇌허혈에서 성향정기산과 곽향정기산이 신경세포에 미치는 효과)

  • 김선영;이원철
    • The Journal of Korean Medicine
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    • v.22 no.4
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    • pp.142-150
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    • 2001
  • Objectives : The purpose of this investigation is to evaluate and compare the effects of Sunghyangjunggi-san (SH) and Gwackhyangjunggi-san (GH) extracts on reperfusion following the MCA occlusion in rats. Methods : To evaluate the effect of Sunghyangjunggi-san (SH) and Gwackhyangjunggi-san (GH) extracts on reperfusion following the MCA occlusion, the volume of cerebral infarction and edema were measured and the change of the CA1 pyramidal neurons in the hippocampus were investigated by light microscopy. Results : 1. The infarction volume of the control group was 23.6%, that of the GH group was 23.7%, and that of the SH group was 18.5%. 2. The brain edema volume of the control group increased by 16% compared with that of the normal group, that of the GH group increased by 14%, and that of the SH group increased by 9%. 3. The number of surviving pyramidal neurons in the CAI area of the hippocampus was investigated under light microscopy. In the control group, few surviving pyramidal neurons excisted (mean 6.4) and similarly in the GH group (mean 8.5), but in the SH group, the number of surviving pyramidal neurons was significantly higher, to the mean 18.4. Conclusions : According to the above results, in regard to the damage of neurons following cerebral ischemia, the GH group has little effect of the protection of neurons compared to the control group, but the SH group has a remarkable effect.

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Effect of the bee venom aqua-acupuncture on the neuronal activities of serotonergic system in brainstem (봉독약침자극(蜂毒藥鍼刺戟)이 뇌간(腦幹) 신경세포(神經細胞)와 Serotonin성(性) 신경세포(神經細胞)의 활성변화(活性變化)에 미치는 영향)

  • Kim, Hye-Nam;Koh, Hyung-Kyun;Park, Dong-Suk;Kang, Sung-Keel;Kim, Yong-Suk;Choi, Yong-Tae
    • Journal of Acupuncture Research
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    • v.17 no.2
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    • pp.119-138
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    • 2000
  • This study was designed to evaluate the effect of the bee venom(BV) aqua-acupuncture on the neuronal activities of serotonergic(5-HT) system in the brainstem. After the BV aqua-acupuncture was applied on Chok-Samni(ST36) and the gluteal part(Blank locus) in rats, the number of Fos immunoreactive neurons was counted by using computerized image analyzing system. Also, the number of colocalization between 5-HT containing neurons Fos immunoreactive neurons were analyzed by using the double immunohistochemical technique. The results of the experiments were summarized as follows : 1. In almost every neucli, the Chok-Samni group and Blank locus group showed more increase in the number of Fos immunoreactive neurons than the control group. Especially, in Arc, DR, LC, RMg, Gi, PAG Rost and PAG LV, the Chok-Samni group showed more significant increase than the control group. Also, in PAG LV Mid and Arc, Chok-Samni group showed more significant increase than the Blank locus group. 2. In DR and PAG LV Mid, Chok-Samni group and the Blank locus group showed more significant increase in the number of colocalization between 5-HT containing neurons and Fos immunoreactive neurons than the control group after the BV aqua- acupuncture. Also, the Chok-Samni group showed more significant increase than the Blank locus group. Consequently, the BV aqua-acupuncture increased more potent the number of Fos immunoreactive neurons and the activity of serotonergic neurons. Furthermore, the BV aqua-acupuncture was more effective on Chok-Samni than Blank locus group. These results indicate that the BV aqua-acupuncture is very effective therapy to control pain. The therapeutic effect of BV aqua-acupunture may associated with the endogenous modulatory system such as serotonin Those data from the study can be applied to establish the effective treatment of the BV for pain control in the clinical field.

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New criteria to fix number of hidden neurons in multilayer perceptron networks for wind speed prediction

  • Sheela, K. Gnana;Deepa, S.N.
    • Wind and Structures
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    • v.18 no.6
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    • pp.619-631
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    • 2014
  • This paper proposes new criteria to fix hidden neuron in Multilayer Perceptron Networks for wind speed prediction in renewable energy systems. To fix hidden neurons, 101 various criteria are examined based on the estimated mean squared error. The results show that proposed approach performs better in terms of testing mean squared errors. The convergence analysis is performed for the various proposed criteria. Mean squared error is used as an indicator for fixing neuron in hidden layer. The proposed criteria find solution to fix hidden neuron in neural networks. This approach is effective, accurate with minimal error than other approaches. The significance of increasing the number of hidden neurons in multilayer perceptron network is also analyzed using these criteria. To verify the effectiveness of the proposed method, simulations were conducted on real time wind data. Simulations infer that with minimum mean squared error the proposed approach can be used for wind speed prediction in renewable energy systems.

RESPONSE CHARACTERISTICS OF VENTRAL POSTEROMEDIAL THALAMIC NOCICEPTIVE NEURONS IN THE ANESTHETIZED RAT (마취된 흰 쥐 시상의 복후내측핵내 유해성 뉴론의 특성)

  • Lee, Hyung-Il;Park, Soo-Joung
    • Restorative Dentistry and Endodontics
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    • v.27 no.6
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    • pp.587-599
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    • 2002
  • Extracellular single unit recordings were made from the ventral posteromedial thalamic (VPM) nociceptive neurons to determine mechanoreceptive field (RF) and response properties. A total of 44 VPM thalamic nociceptive neurons were isolated from rats anesthetized with urethane-chloralose. Based on responses to various mechanical stimuli including touch, pressure and pinch applied to the RF, 32 of 44 neurons were classified as nociceptive specific (NS) neuron. The other 12 neurons, classified as wide dynamic range (WDR), showed a graded response to increasingly intense stimuli, with a maximum discharge to noxious pinch. The VPM nociceptive neurons showed various spontaneous activity ranged from 0-6 Hz. They were located throughout the VPM, and had an contralateral RF including mainly intraoral (and perioral) regions. The RF size was relatively small, and very few neurons had a receptive field involving 3 trigeminal divisions. The NS neurons activated only by pressure and pinch stimuli had high mechanical thresholds compared to WDR neurons activated also by touch stimuli. The VPM nociceptive neurons were tested with suprathershold graded mechanical stimuli. Most of 21 NS and 8 WDR neurons showed a progressive increase in number of spikes as mechanical stimulus intensity was increased. In some neurons, the responses reached a peak before the highest intensity was given. Application of 5 mM $CoCl_2{\;}(10{\;}{\mu}\ell)$ solution to the trigeminal subnucleus caudalis did not produce any significant changes in the spontaneous activity, RF size, mechanical threshold, and response to suprathreshold mechanical stimuli of 9 VPM nociceptive neurons tested. 17 of 33 VPM nociceptive neurons responded to noxious heat as well as noxious mechanical stimuli applied to their RF. Application of the mustard oil, a small-fiber excitant and inflammatory irritant, to the right maxillary first molar tooth pulp induced an immediate but short-lasting neuronal discharges upto approximately 4 min in 16 of 42 VPM nociceptive neurons. These results suggest that VPM thalamic nucleus may contribute to the sensory discriminative aspect of orofacial nociception.

Responses of Inferior Olive Neurons to Stimulation of Semicircular Canals

  • Park, Sah-Hoon;Park, Jong-Seong;Lee, Min-Su;Shin, Jung-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.4
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    • pp.193-197
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    • 2002
  • In spite of abundant anatomical evidences for the fiber connection between vestibular nuclei and inferior olivary (IO) complex, the transmission of vestibular information through the vestibulo- olivo-cerebellar climbing fiber pathway has not been physiologically established. The aims of the present study were to investigate whether there are IO neurons specifically responding to horizontal rotation and also in which subregions of IO complex these vestibularly-activated neurons are located. The extracellular recording was made in 68 IO neurons and responses of 46 vestibularly-activated cells were analyzed. Most of the vestibularly-activated IO neurons responded to signals of vertical rotation (roll), while a small number (13/46) of recorded cells were activated by horizontal canal signal (yaw). Regardless of yaw-sensitive or roll-sensitive, vestibular IO neurons were excited, when the animal was rotated to the side contralateral to the recording side. The gain and excitation phase were very similar to otolithic or vertical-canal responses. Histologic identification of recording sites showed that most of vestibular IO neurons were located in ${\beta}$ subnucleus. Electrical stimulation of a HSC evoked an inhibitory effect on the excitability of the ipsilateral IO neurons. These results suggest that IO neurons mainly in the ${\beta}$ subnucleus receive vestibular signals from semicircular canals and otolithic organs, encode them, and transmit vestibular information to the cerebellum.

Immunocytochemical Mapping of Serotonergic Neurons in Postembrvonic Brains of Cabbage Butterfly Pieris rcpce (배추흰나비 유충, 용, 성충의 뇌에 분포하는 세로토닌 면역반응성 신경원)

  • 이봉희;심재원
    • The Korean Journal of Zoology
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    • v.35 no.4
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    • pp.428-438
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    • 1992
  • The serotonin-immunoreactive (5-HTil neurons have been investigated in the brains of lanra, pupa and adult from Pieris ropae. There are ca. 54 5-HTi neurons in 5-instar larva, ca. 20 in 2-dav-old pupa and ca. 118 in 1-day-old adult, respectively. Most of these 5-HTi neurons are interneurons, but efferent and afferent 5-HTi neurons were also observed. Most of the 5-HTi neurons project into the central neuropils of postembrvonic brains. The larval brain contains abundant 5-HTi processes in the central neuropils, including those in three cerebral commissures. But in the pupal brain the 5-HTi processes are restricted in small numbers to the given regions of central neuropil. The adult brain contains a large number of 5-HTi processes in mushroom body, central body complex, lateral protocerebrum, protocerebral bridge, antennal lobe, and tritocerebral and suboesophageal neuropils. However, the 5-HTi processes are not found in the optic lobe of the brains. One prominent feature of the 5-HTi fibers in the postembrvonic brains is the fact that they are greatly arborized.

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Prenatal Development of Tvrosine Hlrdroxvlase-Containing Neurons in the Rat Brain (흰쥐 태아 뇌에서 TH 신경세포의 초기발생과정)

  • 이영기;장가용
    • The Korean Journal of Zoology
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    • v.36 no.2
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    • pp.209-222
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    • 1993
  • The present study attempts to explore the first appearance 8nd subsequent development of %cosine hvdroxvlase (TH)-containing neurons in the rat brain from embryonic day (E) 10.5 to the neonate. To increase the senti노ivity and resolution power, a double bridge peroxidase-anti-peroxidase technique was employed for cellular localization of TH. In situ hybridization histochemistw with synthetic TH oligomer (30-mer) codinB TH was also used to detect TH mRNA. TH-containing neurons were first detected at E11.5 in the intermediate zone of prosencepha1on and mesencephalon. At this stage, TH-immunoreactive neurons were small, ovoid bee and emitted their fibres into their immediate surroundings. From this stage, TH-immunoreactive neurons increased in their number and underwent migration and cell differentiation. At E15.5, the distribution pattern of the maior groups of TH neurons was similar to that of adult catecholaminergic groups, and at E19.5 the external laver of median eminence showed TH-immunoreactive processes.

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