• 제목/요약/키워드: peripheral resistance

검색결과 120건 처리시간 0.025초

뉴로모픽 시스템용 시냅스 트랜지스터의 최근 연구 동향

  • 남재현;장혜연;김태현;조병진
    • 세라미스트
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    • 제21권2호
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    • pp.4-18
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    • 2018
  • Lastly, neuromorphic computing chip has been extensively studied as the technology that directly mimics efficient calculation algorithm of human brain, enabling a next-generation intelligent hardware system with high speed and low power consumption. Three-terminal based synaptic transistor has relatively low integration density compared to the two-terminal type memristor, while its power consumption can be realized as being so low and its spike plasticity from synapse can be reliably implemented. Also, the strong electrical interaction between two or more synaptic spikes offers the advantage of more precise control of synaptic weights. In this review paper, the results of synaptic transistor mimicking synaptic behavior of the brain are classified according to the channel material, in order of silicon, organic semiconductor, oxide semiconductor, 1D CNT(carbon nanotube) and 2D van der Waals atomic layer present. At the same time, key technologies related to dielectrics and electrolytes introduced to express hysteresis and plasticity are discussed. In addition, we compared the essential electrical characteristics (EPSC, IPSC, PPF, STM, LTM, and STDP) required to implement synaptic transistors in common and the power consumption required for unit synapse operation. Generally, synaptic devices should be integrated with other peripheral circuits such as neurons. Demonstration of this neuromorphic system level needs the linearity of synapse resistance change, the symmetry between potentiation and depression, and multi-level resistance states. Finally, in order to be used as a practical neuromorphic applications, the long-term stability and reliability of the synapse device have to be essentially secured through the retention and the endurance cycling test related to the long-term memory characteristics.

16주 저항성 트레이닝이 엘리트 역도선수의 피로물질과 근 손상, 산화적 손상, myokine에 미치 는 영향 (The Effect of 16 Weeks of Resistance Training on the Fatigue Factor, Muscle Soreness, Oxidative Stress, and Myokine in Elite Weightlifters)

  • 김철우;김군도;강성훈;박찬호;김귀백;김영일
    • 생명과학회지
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    • 제22권2호
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    • pp.184-191
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    • 2012
  • 본 연구의 목적은 16주 근력 트레이닝을 동반한 TRX, 코어 훈련이 엘리트 역도 선수의 피로물질과 근 손상, 산화적손상, myokine에 미치는 영향을 규명하기 위함이다. 본 연구 대상자들은 총 10명(남 6명, 여 4명)으로 구성되어 있으며 16주 근력 운동과 더불어 코어 및 TRX 트레이닝을 실시하여 다음과 같은 결과를 얻었다. Ammonia와 Pi는 트레이닝 전에 비해 점차적으로 증가함을 나타냈으나 통계적으로 유의한 차이는 나타나지 않았다. 근 손상 물질인 CK는 트레이닝 전에 비해 8주에 유의한(p<0.05) 증가를 나타냈으며, LDH는 트레이닝 전에 비해 8주에 유의한(p<0.05) 증가를 나타냈지만 16주에는 감소하는 경향을 나타냈다. 산화적 손상 지표인 MDA는 트레이닝전과 16주에 비해 트레이닝 8주에서 유의한(p<0.05) 증가를 나타냈으며, 항산화 지표인 TAS 또한 트레이닝 전에 비해 트레이닝 8주에서 통계적으로 유의한(p<0.05) 증가를 나타냈다. Myokine인 IL-15는 트레이닝 전에 비하여 트레이닝 8주와 16주에 통계적으로 유의한(p<0.05) 증가를 나타냈다. 결과적으로 16주 고강도 근력 트레이닝은 엘리트 중학교 역도선수의 피로물질과 근 손상, 산화적 손상, myokine에는 긍정적이 영향을 미친 것으로 나타났다.

전폐형 유도전동기의 온도분포에 관한 수치 및 실험적 해석 (Numerical and experimental analysis of temperature distribution in TEFC induction motor)

  • 윤명근;고상근;한송엽;이양수
    • 대한기계학회논문집B
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    • 제21권3호
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    • pp.457-472
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    • 1997
  • We studied the temperature distribution and heat transfer characteristics of TEFC induction motor with thermal network program for more efficient design and better cooling performance of it. We knew the characteristics and the windage loss of outer cooling fan from fan test experiments. Frame axial and peripheral heat transfer coefficients and endwinding heat transfer coefficient were measured by various model experiments and then, compared with other experimental results. Frame was the main heat transfer surface, load-side and fan-side surface were not thermally symmetric from the heat flux distribution analysis. Steady and unsteady temperature distributions were measured by real motor experiments. From the results, we knew that rotor surface temperature was higher than coil temperature and the hottest spot in the coil was loadside endwinding outside surface. We compared the simulation results with those of real motor test and the two results showed a good agreement.

고지방식유래의 뇌졸중 유발 고혈압 흰쥐(SHRSP)에 있어서 수용성 식이 섬유의 급여가 근섬유 형태에 따른 GLUT4 발현에 미치는 영향 (Effects of Soluble Dietary Fiber on Skeletal Muscle GLUT4 Protein Contents in SHRSP Fed a High-Fat Diet)

  • 송영주
    • Journal of Nutrition and Health
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    • 제33권7호
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    • pp.712-716
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    • 2000
  • The Purpose of this study is to investigate the effect of soluble dietary fiber psyllium on insulin sensitivity and skeletal muscle glucose transporter 4(GLUT4) protein expression in stroke-prone hypertensive rats(SHRSP) fed a high-fat diet containing 5% of psyllium or cellulose from five to nine weeks of age. Obtained results were as follows : (1) In the psyllium diet group fasting plasma glucose level was significantly reduced and glucose levels upon oral glucose tolerance test were significantly lower than cellulose diet group at 30 min(p<0.05) and 60 min(p<0.01) (2) Skeletal muscle GLUT4 contents were significantly increased in the soleus(slow twitch) and extensor digitorum longus(fast twitch) muscle of psyllium diet group. (3) However there was no difference in insulin levels in the fasting and oral glucose tolerance test. These results indicated that psyllium diet improves peripheral insulin sensitivity but not insulin secretion. In conclusion our present finding suggest that soluble fiber diet is effective to increase insulin sensitivity in SHRSP. From these results it was suggested that soluble dietary fiber supplementation effectively prevents insulin resistance.

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보행 혈압 측정과 심장 기능의 관계 (Relationship between ambulatory blood pressure monitoring and cardiac function)

  • 송영환
    • Clinical and Experimental Pediatrics
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    • 제52권7호
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    • pp.752-755
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    • 2009
  • It is well known that hemodynamic load is one of the most important determinants of cardiac structure and function. Circadian variations in blood pressure (BP) are usually accompanied by consensual changes in peripheral resistance and/or cardiac output. In recent years, reduction in circadian variations in BP and, in particular, loss of nocturnal decline of BP were observed in hypertensive patients with left ventricular hypertrophy (LVH). The patients with only a slight or no loss of nocturnal decline of BP were considered "non-dippers". Regression of LVH was observed after prolonged antihypertensive therapy. Restoration of the circadian rhythm of BP was also observed. However, the classification of patients into "dippers" and "non-dippers" is arbitrary and poorly standardized and repeatable, and in the recent studies, most hypertensive patients with LVH were "dippers". Therefore, we should be particularly cautious about the conclusions drawn using this index. On the other hand, reduced activity of low-pressure cardiopulmonary baroreceptors and impaired day-to-night modulation of autonomic nervous system activity were observed in patients with only LVH. Therefore, alterations in cardiac structure may impair BP modulation. On the other hand, the reverse can also be trueprimary alterations in BP modulation, through a persistently elevated afterload, can increase cardiac mass. Thus, the interrelationship between cardiac structure and BP modulation is complex. Hence, new and more specific methods of evaluating circadian changes in BP are needed to better clarify the abovementioned reciprocal influences.

Effect of the ERCC1 (C118T) Polymorphism on Treatment Response in Advanced Non-Small Cell Lung Cancer Patients Undergoing Platinum-Based Chemotherapy

  • Kaewbubpa, Walennee;Areepium, Nutthada;Sriuranpong, Virote
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권11호
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    • pp.4917-4920
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    • 2016
  • For advanced non-small-cell lung cancer (NSCLC) cases, a platinum-based regimen is the first-line chemotherapy treatment. The excision repair cross-complementing group 1 (ERCC1) plays an important role in DNA repair and has been related to resistance to platinum chemotherapy. This study aimed to investigate the effects of the ERCC1 (C118T) polymorphism on treatment response in 26 Thai advanced NSCLC patients receiving first line platinum-based chemotherapy during January to July 2015 at King Chulalongkorn Memorial Hospital (KCMH). DNA was extracted from peripheral blood lymphocytes and the single nucleotide polymorphism of ERCC1 was genotyped using a real-time PCR method with the TaqMan assay. The distribution of C/C, C/T and T/T genotypes was 57.7 %, 34.6 % and 7.7 %, respectively. The response rate to platinum-based chemotherapy in the wild type (C/C) of ERCC1 (C118T) was better than with the variant types (C/T and T/T) but the difference was not statistically significant (29.7% vs 9.1%, P=0.274). The results showed that a genetic polymorphism in ERCC1 might influence patient response to platinum-based chemotherapy. Further multicenter studies are now required to confirm the results of our study.

좌귀음과 육미지황탕 전탕액 투여가 가토신기능 및 혈장 Aldosterone농도에 미치는 영향 (Effect of Choakwiyeum and Yukmijihwang-tang Water Extract on the Renal Aldosterone Concentration in Rabbits)

  • 최우정;이언정;김형균;이광석;이대용;정대영
    • 동의생리병리학회지
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    • 제16권6호
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    • pp.1263-1269
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    • 2002
  • To evaluate the effect of Choakwiyeum(CKY) and Yukmijihwang-tang(YJT) water extract on the renal function and the levels of plasma aldosterone, this experiment was performed in the rabbbits. These result indicate that increase in urine volume(UV) after administration of CKY and YJT water extract is related to increase in glomerular filtration rate(GFR), free water clearance(FWC) and renal plasma f1ow(RPF) and also to decrease in plasma aldosterone concentration(PAC), which seems to be affected by renin-angiotensin-aldosterone system, and that reduced blood pressure seems to be caused by reduced peripheral resistance.

Identification of troglitazone responsive genes: induction of RTP801 during troglitazone-induced apoptosis in Hep 3B cells

  • Kim, Jin-Oh;Kim, Ji-Young;Kwack, Mi-Hee;Hong, Su-Hyung;Kim, Moon-Kyu;Kim, Jung-Chul;Sung, Young-Kwan
    • BMB Reports
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    • 제43권9호
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    • pp.599-603
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    • 2010
  • Troglitazone is an anti-diabetic agent that improves hyperglycemia by reducing peripheral insulin resistance in type II diabetic patients. Troglitazone has been shown to cause growth inhibition of various normal and cancerous cells. However, the molecular mechanism by which troglitazone affects the growth of these cancer cells remains unclear. Here, we report that troglitazone treatment of Hep 3B human hepatocellular carcinoma cells resulted in dose-dependent growth inhibition. Analysis of cell cycle distribution by flow cytometry showed that the number of apoptotic cells was increased in a dose-dependent manner in response to troglitazone treatment. cDNA microarray analysis showed a number of differentially expressed genes in response to troglitazone. Among the upregulated genes, hypoxia-inducible factor 1 (HIF-1)-responsive RTP801 was induced in a dose-dependent manner. We also observed HIF-1 accumulation by immnocytochemistry after troglitazone treatment. These results strongly suggest that RTP801 might be involved in troglitazone-induced apoptosis in Hep 3B cells.

만성(慢性) 간(肝) 질환(疾患)에서 경구적(經口的) 당부하(糖負荷) 시험시(試驗時) 혈당(血糖) 및 혈장(血漿) 인슐린의 변동(變動)에 관(關)한 연구(硏究) (A Study on the Glucose and Immunoreactive Insulin Response during Oral Glucose Tolerance Test in Patients with Chronic Liver Diseases)

  • 최강원;이홍규;고창순;이문호
    • 대한핵의학회지
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    • 제7권1호
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    • pp.31-38
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    • 1973
  • The blood glucose and plasma immunoreactive insulin(IRI) levels were measured glucose tolerance test in 7 healthy subjects and 6 patients with chronic liver diseases. The glucose tolerance was impaired in 5 of the 6 patients and normal in 1. Plasma IRI responses were markedly increased and delayed in all patients, suggesting insulin resistance. Patients with more glucose intolerance showed less increase in plasma IRI than the group with less intolerance. It is suggested that some insulin antagonists may decrease the peripheral insulin sensitivity and stimulate compensatory hyperactivity of pancreatic islets. If the compensatory hyperactivity is inadequate due to genetic predisposition to diabetes mellitus or exhaustion of ${\beta}$-cells of pancreatic islsts, the glucose intolerance and overt diabetes mellitus may ensue.

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곽향정기산(藿香正氣散)이 가토(家兎)의 수축혈관에 마치는 영향(影響) (Effects of GwakHyangJungGiSan on the Arterial Contraction in Rabbit)

  • 선중기;김호현;남창규;구창모
    • 대한한방내과학회지
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    • 제24권2호
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    • pp.260-268
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    • 2003
  • Object : This study was undertaken to define the mechanism of GwakHyangJungGiSan-induced relaxation in rabbit common carotid artery contracted by agonists. Method : In order to investigate the effect of GwakHyangJungGiSan on rabbit's contracted vascular ring detached from common carotid artery, vascular ring intact or damaged endothelium was used for the experiment using organ bath. To analyze the mechanism of GwakHyangJungGiSan-induced relaxation, GwakHyangJungGiSan extract was infused into contracted vascular ring which had been pretreated by pretreatment of indomethacin(IM), tetraethylammonium chloride(TEA), $N{\omega}-nitro-L-arginine(L-NNA)$. Result : GwakHyangJungGiSan blocks an inflow of $Ca^{2+}$ and relaxes vascular ring by the action of Nitric oxide from endothelium. Consequently when GwakHyangJungGiSan is prescribed, a rise in blood pressure by the resistance of peripheral vessel may be controlled to some extent and so it is anticipated that hypertension, a disorder of blood flow from the vascular contraction and vascular disease will be treated well.

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