• Title/Summary/Keyword: node activity

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The Gradient Model of the Rabbit Sinoatrial Node

  • Dobrzynski, H.;Lei, M.;Jones, S.A.;Lancaster, M.K.;Boyett, M.R.
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.4
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    • pp.173-181
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    • 2002
  • The sinoatrial (SA) node is a complex and inhomogeneous tissue in terms of cell morphology and electrical activity. There are two models of the cellular organisation of the sinoatrial node: the gradient and mosaic models. According to the gradient model there is a gradual transition in morphology and electrical properties of SA node cells from the centre to the periphery of the SA node. In the mosaic model, there is a variable mix of atrial and sinoatrial node cells from the centre to the periphery. This review focuses on the cellular organisation of the rabbit sinoatrial node in terms of the expression of connexin (Cx40, Cx43 and Cx45), L-type $Ca^{2+}$ channel and $Na^+-Ca^{2+}$ exchanger proteins. These immunocytochemical data, together with morphological and electrophysiological data, obtained from the intact sinoatrial node and isolated sinoatrial node cells support the gradient model of the cellular organisation of the SA node. The complex organisation of the sinoatrial node is important for the normal functioning of the sinoatrial node: (i) it allows the sinoatrial node to drive the surrounding hyperpolarized atrial muscle without being suppressed by it; (ii) it helps the pacemaker activity of the sinoatrial node continue under a wide range of physiological and pathophysiological conditions; (iii) it helps protect the sinoatrial node from reentrant arrhythmias.

Interference and Sink Capacity of Wireless CDMA Sensor Networks with Layered Architecture

  • Kang, Hyun-Duk;Hong, Heon-Jin;Sung, Seok-Jin;Kim, Ki-Seon
    • ETRI Journal
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    • v.30 no.1
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    • pp.13-20
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    • 2008
  • We evaluate the sink capacity of wireless code division multiple access (CDMA) sensor networks with layered architecture. We introduce a model of interference at a sink considering two kinds of interference: multiple access interference (MAI) and node interference (NI). We also investigate the activity of sensor nodes around the sink in relation to gathering data under a layered architecture. Based on the interference model and the activity of sensor nodes around the sink, we derive the failure probability of the transmission from a source node located one hop away from the sink using Gaussian approximation. Under the requirement of 1% failure probability of transmission, we determine the sink capacity, which is defined as the maximum number of concurrent sensor nodes located one hop away from the sink. We demonstrate that as the node activity of the MAI decreases, the variation of the sink capacity due to the node activity of the NI becomes more significant. The analysis results are verified through computer simulations.

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Decision method for rule-based physical activity status using rough sets (러프집합을 이용한 규칙기반 신체활동상태 결정방법)

  • Lee, Young-Dong;Son, Chang-Sik;Chung, Wan-Young;Park, Hee-Joon;Kim, Yoon-Nyun
    • Journal of Sensor Science and Technology
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    • v.18 no.6
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    • pp.432-440
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    • 2009
  • This paper presents an accelerometer based system for physical activity decision that are capable of recognizing three different types of physical activities, i.e., standing, walking and running, using by rough sets. To collect physical acceleration data, we developed the body sensor node which consists of two custom boards for physical activity monitoring applications, a wireless sensor node and an accelerometer sensor module. The physical activity decision is based on the acceleration data collected from body sensor node attached on the user's chest. We proposed a method to classify physical activities using rough sets which can be generated rules as attributes of the preprocessed data and by constructing a new decision table, rules reduction. Our experimental results have successfully validated that performance of the rule patterns after removing the redundant attribute values are better and exactly same compare with before.

CLINICAL IMPLICATIONS OF TELOMERASE ACTIVITY IN ORAL SQUAMOUS CELL CARCIMOMA (구강편평세포암에서 telomerase 활성도의 임상적 연관성에 관한 연구)

  • Shim, Yu-Jin;Kim, Myung-Jin;Nahm, Dong-Seok;Lee, Jong-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.27 no.4
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    • pp.289-300
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    • 2001
  • Telomerase is a ribonucleoprotein that synthesizes telomere repeats. It has been reported that activation of telomerase was associtated with immortalization, proliferative activity and carcinogenesis. Recently, telomerase activity has been extensively studied in many kinds of malignant tumors for clinical diagnostic and/or prognostic utilities. In neuroblastoma, breast carcinoma, gastric carcinoma, non-small cell lung carcinoma, close relationship has been reported between high telomerase activity and lymph node metastasis, tumor aggressiveness and poor prognosis. The purpose of this study is to investigate the clinical implication of telomerase activity assay as an adjunctive factor in decision-making on neck node management, speedy pre-operative judging on histologic malignancy grading. Thus we performed semi-quantitative assay of telomerase activity using Telomerase PCR ELISA $kit^{(R)}$(Boeringer Manheim, Germany) and evaluated correlation between telomerase activity and tumor size, neck node metastasis, Anneroth malignancy score and influence of pre-operative chemotherapy on its activity in 27 cases of oral squamous cell carcinomas and 18 cases of normal oral epithelium. Also, correlation between telomerase activities and PCNA indices was evaluated. The results were obtained as follows: 1. The telomerase activities were detected in 24 specimens out of 27 oral squamous cell carcinoma specimens (88.9%) and in 5 specimens out of 18 normal oral epithelium specimens (27.8%). The mean value of telomerase activities was $0.9793{\pm}0.3428$ in 24 oral squamous cell carcinoma specimens and $0.4855{\pm}0.1117$ in 5 normal oral epithelium specimens. The positivity rate and mean value of telomerase activities in oral squamous cell carcinoma specimens were significantly higher than those of normal oral epithelium specimens (p<0.05). 2. There was no significant correlation between total Anneroth malignancy score and telomerase activity (p>0.05), but points of mitosis index and depth of invasion were significantly correlated with telomerase activities (p<0.05). 3. The positive immunohistochemical staining for PCNA(proliferating cell nuclear antigen) was observed in 26 specimens out of 27 oral squamous cell carcinoma specimens and mean value of PCNA indices of 26 specimens was $53.67{\pm}26.46$. PCNA indices were significantly correlated with telomerase activities (p<0.05). 4. The mean value of telomerase activities was significantly higher in pathologic T3/T4 group than in T1/T2 group (p<0.01). There was no significant difference of mean value of telomerase activities between pathologic neck node positive group and negative group (p> 0.05). Pre-operative chemotherapy significantly lowered the telomerase activities (p<0.05). The above results suggested telomerase activity could be used as diagnostic marker and adjunctive parameter for judging on histologic malignancy in oral squamous cell carcinoma.

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A Research for Removing ECG Noise and Transmitting 1-channel of 3-axis Accelerometer Signal in Wearable Sensor Node Based on WSN (무선센서네트워크 기반의 웨어러블 센서노드에서 3축 가속도 신호의 단채널 전송과 심전도 노이즈 제거에 대한 연구)

  • Lee, Seung-Chul;Chung, Wan-Young
    • Journal of Sensor Science and Technology
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    • v.20 no.2
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    • pp.137-144
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    • 2011
  • Wireless sensor network(WSN) has the potential to greatly effect many aspects of u-healthcare. By outfitting the potential with WSN, wearable sensor node can collects real-time data on physiological status and transmits through base station to server PC. However, there is a significant gap between WSN and healthcare. WSN has the limited resource about computing capability and data transmission according to bio-sensor sampling rates and channels to apply healthcare system. If a wearable node transmits ECG and accelerometer data of 4 channel sampled at 100 Hz, these data may occur high loss packets for transmitting human activity and ECG to server PC. Therefore current wearable sensor nodes have to solve above mentioned problems to be suited for u-healthcare system. Most WSN based activity and ECG monitoring system have been implemented some algorithms which are applied for signal vector magnitude(SVM) algorithm and ECG noise algorithm in server PC. In this paper, A wearable sensor node using integrated ECG and 3-axial accelerometer based on wireless sensor network is designed and developed. It can form multi-hop network with relay nodes to extend network range in WSN. Our wearable nodes can transmit 1-channel activity data processed activity classification data vector using SVM algorithm to 3-channel accelerometer data. ECG signals are contaminated with high frequency noise such as power line interference and muscle artifact. Our wearable sensor nodes can remove high frequency noise to clear original ECG signal for healthcare monitoring.

Effect of ethanol extract of Lotus Rhizome and node of Lotus Rhizome (연근과 우절 에탄올 추출물의 향장효능 검증)

  • Jang, Young-Ah;Park, So-Hyun;Kim, Bo-Ae;Park, Jong-Yi;Jeoung, Young-Ok;Lee, Jin-Tae
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.3
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    • pp.657-665
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    • 2017
  • This study is for checking the possibility of Lotus Rhizome and node of Lotus Rhizome as cosmetic materials. For this we carried out biological active evaluation about anti-oxidant, anti-inflammatory and anti-wrinkle by using ethanol extract of Lotus Rhizome and node of Lotus Rhizome. We extracted Lotus Rhizome and node of Lotus Rhizome with 95% ethanol and then in order to evaluate anti-oxidant activity we treated samples by concentrations (100, 500, 1000) ${\mu}g/mL$ and carried out 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and The activity of 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) cation radical scavenging. Also, in order to evaluate effect of anti-wrinkle we carried out evaluation of Elastase inhibitory activity. To evaluate effect of anti-inflammatory we evaluated toxicity of samples through MTT assay with a macrophage (Raw 264.7 cells) and measured nitric oxide production inhibitory activity. As a result, DPPH radical scavenging activity of Lotus Rhizome and node of Lotus Rhizome at $1000{\mu}g/mL$ was 66.7% and 99.5%, respectively and ABTS + radical scavenging activity was 51.2% and 98.3% at the same concentration, respectively. Elastase inhibitory activity results showed that the nodes of the Lotus Rhizom extract excellent anti-wrinkle efficacy than Lotus Rhizom. Node of Lotus Rhizome showed higher anti-wrinkle activity than the positive the control group BHT at $1000{\mu}g/mL$ concentration. According to the result of nitric oxide production inhibitory activity, Lotus Rhizom showed 55.8% effect and nodes of the Lotus Rhizom showed 66.6% effect respectively. This showed that effect of anti-inflammatory was greater in nodes of the Lotus Rhizom extracts. As a result it suggests that Lotus Rhizome and node of Lotus Rhizome extracts can be used as natural substance of cosmetics which are safe in antioxidant, anti-inflammatory, and anti-wrinkle.

Effect of Foliar Application of Uniconazol and Paclobutrazol on Growth and Yield of Codonopsis lanceolata (Uniconazol 및 Paclobutrazol의 葉面散布 처리가 더덕의 생육 및 수량에 미치는 영향)

  • 김학현
    • Korean Journal of Plant Resources
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    • v.10 no.4
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    • pp.411-417
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    • 1997
  • In order to improve cultivation technique of Codonopsis lanceolata, uniconazol and paclobutrazol were treated periodically with foliar application during differentiation of node. Plant height, width and length of leaves decreased as the concentration of uniconazol and paclobutrazol increased independently of application period. Characteristics of subterranean part of all treatment by uniconazol foliar application did not show any significant difference to control, except when treated at the differentiated stage of 3rd node. But, when uniconazol was treated with the concentration of 10, 100mg $liter^1$, respectively at the differentiated stage of 12th node, fresh weight was increased to approximately 64%, 100% of control, respectively. Control and 10mg $liter^1$ treated at the differented stage of 6th node showed antitumor activity by the P388 cytotoxic screening test. Fresh weight of all treatment by paclobutrazol foliar application was not showed signigicant difference to control, except when treated at the differentiateed stage of 3rd node. But, when paclobutrazol was treated with the concentration of 10mg $liter^1$ at the differentiated stage of 12th node, fresh weight was slightly increased of control. All treatment showed slight antitumor activity by the P388 cytotoxic screening test.

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Anti-diabetic Constituent from the Node of Lotus Rhizome (Nelumbo nucifera Gaertn)

  • Lee, Min-Won;Kim, Jun-Sik;Cho, Su-Min;Kim, Ji-Hun;Lee, Jae-Seung
    • Natural Product Sciences
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    • v.7 no.4
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    • pp.107-109
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    • 2001
  • To investigate anti-diabetic component from the node of lotus rhizome (Nelumbo nucifera; Nymphaeaceae), activity guided isolation was conducted. One amino acid was isolated from active fraction of the aqueous methanolic extract. The structure of this compound was identified as tryptophan (1) by the analysis of spectroscopic evidences and comparisons with the data of authentic samples. Tryptophan reduced the blood glucose level significantly in glucose-fed hyperglycemic mice compared with glucose-treated group and exhibited 44.3% of activity compared with tolbutamide,.

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Development of Daily Life Monitori ng System using RFID (RFID를 이용한 일상생활 모니터링 시스템 개발)

  • Jung, Kyung-Kwon;Park, Hyun-Sik;Choi, Woo-Seung
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.7
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    • pp.49-56
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    • 2009
  • In this paper, we present a daily activity monitoring system by using a wireless sensor network. The proposed system is installed in glove for activity monitoring. The RFID reader, to send data by using sensor network platform and RFID tag are small size, the shape of quadrangle, and operate in the frequency of 13.56 MHz. The sensor node can read RFID tags on the various objects used in daily living such as furniture, medicines, and kitchenwares. The sensor node reads the data of RFID tags, it transmits wireless packets to the sink node. The sink node sends the received packet immediately to a server system. The data from each RFID system is collected into a database, and then the data are processed to visualize the measurement of daily living activities of users. We provide a web-based monitoring system, and can see the number of RFID tag readings per day as bar charts. The result of experiments demonstrates that the way we propose can help to check the situation of life for people who live alone.

Isolation and Characterization of an Immunopotentiating Factor from Lactobacillus plantarum in Kimchi: Assessment of Immunostimulatory Activities

  • Lee, Jong-Hwa;Kweon, Dae-Hyuk;Lee, Seung-Cheol
    • Food Science and Biotechnology
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    • v.15 no.6
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    • pp.877-883
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    • 2006
  • The immunostimulatory activities of Lactobacillus plantarum, the major microorganism in kimchi fermentations were investigated. Five strains of L. plantarum exhibited weak immunopotentiating activity, but L. plantarum PS-21 showed as strong a mitogenic activity as Bifidobacterium adolescentis M101-4, a known positive strain. It is of interest that, L. plantarum PS-21 stimulated proliferation of Peyer's patch cells, one of the most important tissues in the gut-associated lymphoreticular system. Cell' wall fractions from L. plantarum PS-21 also showed strong mitogenic activity compared with the soluble cytoplasmic fraction. A peptidoglycan fraction (PG) extracted from the cell wall of L. plantarum PS-21 was identified as an active mitogenic component when used in murine lymph node and spleen cell test systems. PG showed dose-dependent mitogenic activity and significantly enhanced antibody production in lymph node cells when studied in vitro. The lysosomal enzyme activity of murine peritoneal macrophages was increased when analyzed following injection of PG to the host animal. Furthermore, PG enhanced the production of cytokines such ($TNF-{\alpha}$ and IL-6) in the in vitro culture of RAW 264.7 macrophage cells.