• The Korean Journal of Physiology and Pharmacology
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• 제7권4호
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• pp.217-221
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• 2003

To clarify the roles of gonadal steroids on pancreatic exocrine secretion, effects of progesterone and estradiol-$17{\beta}$ on spontaneous and secretagogue-induced exocrine response of isolated perfused rat pancreas were investigated. Intra-arterial infusion of progesterone resulted in significant increase of the spontaneous pancreatic fluid and amylase secretion dose-dependently. However, estradiol-$17{\beta}$ did not exert any influence on spontaneous pancreatic exocrine secretion. Exogenous secretin, cholecystokinin (CCK), and acetylcholine markedly stimulated pancreatic fluid and amylase secretion. Progesterone initially enhanced secretin-induced amylase secretion, but this stimulatory response declined thereafter to basal value. Moreover, secretin-induced fluid secretion was not affected by infusion of progesterone. Therefore, initial increase of secretion-induced amylase secretion by progesterone seems to be a non-specific action by washout effect of secretin. Estradiol-$17{\beta}$ failed to change the secretin-induced fluid and amylase secretion. Both progesterone and estradiol-$17{\beta}$ did not exert any influence on CCK-induced fluid and amylase secretion. Acetylcholine-induced exocrine secretion of isolated perfused pancreas also was not affected by intra-arterial infusion of progesterone or estradiol-$17{\beta}$. It is concluded from the above results that progesterone could enhance the spontaneous pancreatic fluid and amylase secretion of isolated perfused rat pancreas through non-genomic shortterm action, and that these effects could be masked by more potent stimulants such as secretin, CCK, and acetylcholine.

• The Korean Journal of Physiology and Pharmacology
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• 제1권6호
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• pp.657-664
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• 1997

The effects of adenosine, adenosine A1 receptor antagonist (DPCPX), or NMDA receptor antagonist (APV) on the spontaneous release of $[^3H]-5-hydroxytryptamine$ ($[^3H]-5-HT$) during normoxic/normoglycemic or hypoxic/hypoglycemic period were studied in the rat hippocampal slices. The hippocampus was obtained from the rat brain and sliced $400\;{\mu}m$ thickness with the tissue slicer. After 30 min's preincubation in the normal buffer, the slices were incubated for 30 min in a buffer containing $[^3H]-5-HT$ ($0.1\;{\mu}M,\;74{\mu}Ci/8\;ml$) for uptake, and washed. To measure the release of $[^3H]-5-HT$ into the buffer, the incubation medium was drained off and refilled every ten minutes through sequence of 14 tubes. Induction of glucose/oxygen deprivation (GOD; medium depleting glucose and gassed with 95% $N_2/5%\;CO_2$) was done in 6th and 7th tube. The radioactivities in each buffer and the tissue were counted using liquid scintillation counter and the results were expressed as a percentage of the total radioactivities. When slices were exposed to GOD for 20 mins, the spontaneous release of $[^3H]-5-HT$ was markedly increased and this increase of $[^3H]-5-HT$ release was blocked by adenosine ($10\;{\mu}M$) or DL-2-amino-5-phosphonovaleric acid (APV; $30\;{\mu}M$). Adenosine $A_1$ receptor specific antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) exacerbate GOD-induced increase of spontaneous release of $[^3H]-5-HT$. These results suggest that Adenosine may play a role in the GOD-induced spontaneous release of $[^3H]-5-HT$ through adenosine $A_1$ receptor activity.

• 청정기술
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• 제22권4호
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• pp.299-307
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• 2016

These days, coal is one of the most important energy resources used for transportation, industry, and electricity. There are two types of coal: high-rank and low-rank. Low-rank coal has a low calorific value and contains large amounts of useless moisture. The quality of low-rank coal can be increased by simple drying technology and it needs to be stabilized by hydrocarbons (e.g. palm acid oil, PAO) to prevent spontaneous combustion and moisture re-adsorption. Spontaneous combustion becomes a major problem during coal mining, storage, and transportation. It can involve the loss of life, property, and economic value; reduce the quality of the coal; and increase greenhouse gas emissions. Besides spontaneous combustion, moisture re-adsorption also leads to a decrease in quality of the coal due to its lower heating value. In this work, PAO was used for additive to stabilize the upgraded coal. The objectives of the experiments were to determine the stabilization characteristic of coal by analyzing the behavior of upgraded coal by drying and PAO addition regarding crossing-point temperature of coal, the moisture behavior of briquette coal, and thermal decomposition behavior of coal.

• 대한상부위장관⦁헬리코박터학회지
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• 제18권3호
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• pp.204-208
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• 2018

Spontaneous intramural hematoma is a rare complication of oral anticoagulants, and its incidence is expected to increase because of the increasing number of elderly patients undergoing anticoagulant therapy. Clinical manifestations of spontaneous intramural hematoma vary from mild abdominal pain to intestinal obstruction or acute abdomen. Early diagnosis is important because most patients can be treated successfully without surgery. The role of endoscopy in the diagnosis of intramural hematoma is not well established because almost all cases are diagnosed non-invasively with computed tomography scans. However, confirmation of the intramural hematoma through direct visualization of the involved bowel mucosa is helpful, if the imaging diagnosis is uncertain. We report a case of anticoagulant-induced spontaneous intramural hematoma, which was diagnosed using endoscopy, with relevant literature review.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.83-85
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• 2013

With an increase in the use of low rank coals in power plants, various operational issues were raised in the fuel storage and supply, combustion, boiler and flue gas treatment systems. In the fuel storage and supply system, the main issue is the self-heating propensity of low rank coals leading to spontaneous combustion in yard storage, transport and pulverization. This study evaluated the reactivity of various sub-bituminous and bituminous coals with oxygen at low temperatures by analyzing the temperature increase characteristics of coals under a constant flow rate of oxygen supply. The results were quantified to a self-heating index and the relation with the fuel properties were evaluated.

• 정보처리학회 논문지
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• 제13권6호
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• pp.284-290
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• 2024

음성감정인식(Speech Emotion Recognition, SER)은 사용자의 목소리에서 나타나는 떨림, 어조, 크기 등의 음성 패턴 분석을 통하여 감정 상태를 판단하는 기술이다. 하지만, 기존의 음성 감정인식 연구는 구현된 시나리오를 이용하여 제한된 환경 내에서 숙련된 연기자를 대상으로 기록된 음성인 구현발화를 중심의 연구로 그 결과 또한 높은 성능을 얻을 수 있지만, 이에 반해 자유발화 감정인식은 일상생활에서 통제되지 않는 환경에서 이루어지기 때문에 기존 구현발화보다 현저히 낮은 성능을 보여주고 있다. 본 논문에서는 일상적 자유발화 음성을 활용하여 감정인식을 진행하고, 그 성능을 향상하고자 한다. 성능평가를 위하여 AI Hub에서 제공되는 한국인 자유발화 대화 음성데이터를 사용하였으며, 딥러닝 학습을 위하여 1차원의 음성신호를 시간-주파수가 포함된 2차원의 스펙트로그램(Spectrogram)로 이미지 변환을 진행하였다. 생성된 이미지는 CNN기반 전이학습 신경망 모델인 VGG (Visual Geometry Group) 로 학습하였고, 그 결과 7개 감정(기쁨, 사랑스러움, 화남, 두려움, 슬픔, 중립, 놀람)에 대해서 성인 83.5%, 청소년 73.0%의 감정인식 성능을 확인하였다. 본 연구를 통하여, 기존의 구현발화기반 감정인식 성능과 비교하면, 낮은 성능이지만, 자유발화 감정표현에 대한 정량화할 수 있는 음성적 특징을 규정하기 어려움에도 불구하고, 일상생활에서 이루어진 대화를 기반으로 감정인식을 진행한 점에서 의의를 두고자 한다.

• 한국세라믹학회지
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• 제35권7호
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• pp.685-690
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• 1998

Al2O3에 대한 용융 Al의 자발적 침윤 기구를 밝히기 위하여 순수한 Al 및 Al-(Si)-Mg 합금의 Al2O3에 대한 wet-ting angle과 침윤 특성을 진공, 아르곤, 그리고 질소분위기에서 관찰하였다. Al2O3에 대한 용융 Al 및 Al 합금의 wetting은 진공 분위기에서만 이루어졌으나, Al2O3에 대한 용융 Al 합금의 자발적 침윤은 질소 분위기하 Al 합금에 합금 원소로써 Mg가 함유되었을 때에 일어났다. Al2O3에 대한 용융 Al 및 Al 합금의 wettability와 자발적 침윤 특성의 차이는 Al2O3 표면에 형성되는 Mg-N화합물에 직접적인 영향을 받는 것으로 나타났다. Al2O3 입자 표면에 얇게 형성되는 Mg와 질소의 화합물 즉, Mg3N2가 Al2O3에 대한 용윤 Al 합금의 wettability를 향상시켜 $700^{\circ}C$의 온도에서도 Al 합금의 자발적 침윤이 가능하여 Al/Al2O3 복합재료를 무가압 상태에서 제조할 수 있었다.

• Journal of Preventive Medicine and Public Health
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• 제18권1호
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• pp.41-50
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• 1985

To find out the differences in medical practice according to the environment of patient care and managerial situation of the medical care institutions, normal spontaneous vaginal delivery and acute appendicitis were selected, which is suitable for comparison because of their high comparability. A total of 473 cases of normal spontaneous vaginal delivery and 408 cases of acute appendicitis was sampled from the claims to Korea Medical Insurance Cooperations during January to June 1984. Complicated cases were excluded from population and sampling was restricted from 40 to 60 percentile for total charges by the type of medical care facility in order to rule out the influence originating from case mix. Important items representing type and quantity of medical care service were compared by type of facility. Major findings are as follows : 1. University hospital shows the highest in charges per case and decrease in order of general hospital, and clinic. 2. In case of normal spontaneous vaginal delivery, average length of stay shows statistically significant difference by type of facility. 3. Charge amount for each service item affected by practice pattern shows statistically significant difference mostly by type of facility. It is suggested that medical practice pattern is different by type of facility for medical services. 4. Difference in total medical expenditure by type of facility is affected more with charges for materials, consumables and drugs than with fee for service activity. 5. In administering drugs to patients, hospital and clinic show higher injection rate than university and general hospital. 6. Clinical Laboratory tests were common in order of uninalysis, hemoglobin, hematocrit, white blood cell count, urine microscopic examination in cases of normal spontaneous vaginal delivery; white blood cell count, urinalysis, hemoglobin, hematocrit, urine microscopic examination, white blood cell differential count, in cases of acute appendicitis. 7. The result for Laboratory test and Radiologic study shows extreme difference by type of facility. Test rate is lowest in clinic and increase hospital, general hospital, and university hospital in order, both in type and frequency.

• The Korean Journal of Physiology and Pharmacology
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• 제4권1호
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• pp.1-8
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• 2000

To investigate the contributions of intrinsic membrane properties to the spontaneous activity of medial vestibular nucleus (MVN) neurons, we assessed the effects of blocking large and small calcium-activated potassium channels by means of patch clamp recordings. Almost all the MVN neurons recorded in neonatal $(P13{\sim}P17)$ rat were shown to have either a single deep after-hyperpolarization (AHP; type A cells), or an early fast and a delayed slow AHP (type B cells). Among the recorded MVN cells, immature action potential shapes were found. Immature type A cell showed single uniform AHP and immature B cell showed a lack of the early fast AHP, and the delayed AHP was separated from the repolarization phase of the spike by a period of isopotentiality. Application of apamin and charybdotoxin (CTX), which selectively block the small and large calcium-activated potassium channels, respectively, resulted in significant changes in spontaneous firings. In both type A and type B cells, CTX (20 nM) resulted in a significant increase in spike frequency but did not induce bursting activity. By contrast, apamin (300 nM) selectively abolished the delayed slow AHP and induced bursting activity in type B cells. Apamin had no effect on the spike frequency of type A cells. These data suggest that there are differential roles of apamin and CTX sensitive potassium conductances in spontaneous firing patterns of MVN neurons, and these conductances are important in regulating the intrinsic rhythmicity and excitability.

• Journal of Chest Surgery
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• 제24권9호
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• pp.890-894
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• 1991

We have performed a prospective study to assess the efficacy of suction drainage in 45 patients with primary spontaneous pneumothorax and 15 patients with secondary spontaneous pneumothorax, treated by closed chest tube drainage with underwater seal during the period Jan. 1990 to Dec. 1990 at the Department of Thoracic and Cardiovascular Surgery, Yeungnam University Hospital. The patients were divided randomly into two groups, 28 cases receiving suction and the other 32 cases no suction. The success rate was 82.1% for the former and 87.5% for the latter with the overall success rate of 85.0% and there was no significant difference in success rate between the two groups According to the causes and the extent of pneumothorax, the difference between the success rates of the two groups was also not significant statistically. But according to the duration of air leakage, suction group under 2 days showed a high success rate[46.4%] and the same group with 3-4 days, a relatively low success rate[21.4%] compared with that of the former. We conclude that the suction treatment is somewhat valuable in shortening the tubing time in patients with small amounts of air leakage, but it doesn`t seem to increase the success rate in all patients.