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Expression and Purification of the Phosphatase-like Domain of a Voltage-Sensing Phosphatase, Ci-VSP (막 전위 감지 탈인산화 효소, Ci-VSP의 유사 탈인산화 효소 도메인의 발현과 정제)

  • Kim, Sung-Jae;Kim, Hae-Min;Choi, Hoon;Kim, Young-Jun
    • Journal of Life Science
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    • v.21 no.7
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    • pp.1032-1038
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    • 2011
  • Recently identified Ciona intestinalis voltage sensor-containing phosphatase (Ci-VSP) consists of an ion channel-like transmembrane domain (VSD) and a phosphatase-like domain. Ci-VSP senses the change of membrane potential by its VSD and works as a phosphoinositide phosphatase by its phosphatase domain. In this study, we present the construction of His-tagged phosphatase-like domain of Ci-VSP, its recombinant expression and purification, and its enzymatic activity behavior in order to examine the biochemical behavior of phosphatase domain of Ci-VSP without interference. We found that Ci-VSP(248-576)-His can be eluted with an elution buffer containing 25 mM NaCl and 100 mM imidazole during His-tag purification. In addition, we found the proper measurement condition for kinetics study of Ci-VSP(248-576)-His against p-nitrophenyl phosphate (pNPP). We measured the kinetic constant of Ci-VSP(248-576)-His at $37^{\circ}C$, pH 5.0 or 5.5, under 30 min of reaction time, and less than $2.0\;{\mu}g$ of protein amount. With these conditions, we acquired that Ci-VSP(248-576)-His has $K_m$ of $354{\pm}0.143\;{\mu}M$, $V_{max}$ of $0.0607{\pm}0.0137\;{\mu}mol$/min/mg and $k_{cat}$ of $0.359{\pm}0.009751\;min^{-1}$ for pNPP dephosphorylation. Therefore, we produced a pure form of Ci-VSP(248-576)-His, and this showed a higher activity against pNPP. This purified protein will provide the road to a structural investigation on an interesting protein, Ci-VSP.

The 3-Dimensional Analysis of the Efficacy of a Belly-Board Device for the Displacement of Small Bowel During Pelvic Irradiation (골반강 방사선치료 중 소장의 이동을 위한 벨리보드의 효과에 대한 3차원적 분석)

  • Lee, Kyung-Ja
    • Radiation Oncology Journal
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    • v.26 no.4
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    • pp.271-279
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    • 2008
  • Purpose: To evaluate the efficacy of a belly-board device (BBD) in reducing the volume of small bowel during four-field pelvic irradiation. Materials and Methods: Twenty-two cancer patients (14 uterine cervical cancer, 6 rectal cancer, and 2 endometrial cancer) scheduled to receive pelvic irradiation were selected for this study. Two sets of CT images were taken with and without the belly-board device using the Siemens 16 channel CT scanner. All patients were set in the prone position. The CT images were transferred to a treatment planning system for dose calculation and volume measurements. The external surfaces of small bowel and the bladder were contoured on all CT scans and the 4-pelvic fields were added. The dose-volume-histogram of the bladder and small bowel, with and without the BBD, were plotted and analyzed. Results: In all patients, the total small bowel volume included in the irradiated fields was reduced when the BBD was used. The mean volume reduction was 35% (range, $1{\sim}79%$) and was statistically significant (p<0.001). The reduction in small bowel volume receiving $10{\sim}100%$ of the prescribed dose was statistically significant when the BBD was used in all cases. Almost no change in the total bladder volume involved was observed in the field (<8 cc, p=0.762). However, the bladder volume receiving 90% of the prescribed dose was 100% in 15/22 patients (68%) and $90{\sim}99%$ in 7/22 patients (32%) with the BBD. In comparison, the bladder volume receiving 90% of the prescribed dose was 100% in 10/22 patients (45%), $90{\sim}99%$ in 7/22 patients (32%), and $80{\sim}89%$ in 5/22 patients (23%) without the BBD. When the BBD was used, an increase in the bladder volume receiving a high dose range was observed Conclusion: This study shows that the use of a BBD for the treatment of cancer in the pelvic area significantly improves small bowel sparing. However, since the BBD pushed the bladder into the treatment field, the bladder volume receiving the high dose could increase. Therefore it is recommended to be considerate in using the BBD when bladder damage is of concern.

Studies on- Electrocardiogram of the Normal Korean Native Goat 1. Standard Limb Leads and Unipolar Limb Leads (정상적인 한국 흑염소의 심전도에 관한 연구 1. 표전지유도와 단극지유도)

  • 최인혁;김선기;김추철;최인방;김남수
    • Journal of Veterinary Clinics
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    • v.14 no.2
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    • pp.319-337
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    • 1997
  • The electrocardiographic (ECG) parameters in the normal Korean black goat have been measured with a 3-channel Electrocardiograph and computed, analyzed. ECG in 243 black goats were made with the limb leads (I, II, III, aVR, aVL, aVF), that were recorded conduction parameters of wave and interval, and were analyzed as to shape and amplitude of the P and T waves and the components of the QRS complex. Heart rate were recorded by the ECG which were a mean of 106.1$\pm $21.8 beats/min. Average conduction times in the PR, the QRS complex and the QTc interval were recorded 103.9$\pm $34.9 msec., 58.3$\pm $23.2 msec. and 302.6$\pm $67.8 msec., in the P and T wave duration recorded 24.8$\pm $6.4 msec. and 51.7$\pm $10.8 msec. respectively. The shape of wave in each leads were observed various types, and any spacial wave type appeared the highest frequency in each lead that ware shown less than 60%, and these frequent rate and average amplitudes as fallow: 1. In P waver the frequent rate and average amplitudes of the positive type showed in leads I, II and aVL that were 54.8% (93.0$\pm $ 33.2 $\mu $V), 50.5% (90.1$\pm $30.5 $\mu $V) and 41.7% (58.5$\pm $ 31.1 $\mu $V). Average amplitude of the negative type showed the frequent rate of 49.8% in lead aVE which was -77.6$\pm$ 25.2 $\mu $V. Biphasic type in leads III and aVF were 46.1% (108.4 $\mu $V, -90.2 $\mu $V.) and 45.7% (137.4 $\mu $V, -105.4 $\mu $V.), and amplitudes between positive and negative of it were significant difference. 2. The highest amplitudes of the QRS complex in all leads were 534.8$\pm $ 232.3 $\mu $V of lead II. The frequent rate and amplitudes of the R wave type in the I, II, III and aVF were 30.2% (277.8 $\pm $131.3 $\mu $V), 45.1% (393.1$\pm $114.2 $\mu $V), 48.5% (349.3$\pm $178.3 $\mu $V) and 54.9% (334.4$\pm $129.7 $\mu $V), and QS ways type in the lead aVL was 49.5% (359.2$\pm $195.5$\mu $V), and RS and QS wave types in the lead a VR were 43.3% (312.4 $\mu $V, -212.7 $\mu $V.) and 41.1% (399.2$\pm $92.2 $\mu $V), respectively. 3. In T wave, the frequent rata and amplitudes of the positive type in the leads I, II, III and aVF were 44.6% (207.9$\pm $ 97.1 $\mu $V), 41.6% (245.1$\pm $92.1 $\mu $V), 46.9% (189.8$\pm $ 82.7 $\mu $V) and 53.0% (195.4197.8 $\mu $V), and the negative in the lead aVR was 41.2% (-230.7$\pm$ 103.1 $\mu $V), respectively. The positive and negative types in the lead aVe appeared with same frequent rate of 43.2%.4. Frontal plane vectors for P, QRS, and T were found to lie at 38.1$\pm $ 21.5, 142.0$\pm $ 57.2, and 117.2$\pm $ 63.9 degrees, respectively. These results in ECG of goats may be served to the limited purposes as to conduction parameters, arrhythmias except abnormal ECG because of waveforms, amplitudes and electrical axis of it were variability.

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Flow Resistance of Plane Nettings for Net Cages (우리 그물용 평면 그물감의 유수저항)

  • KIM Tae-Ho;KIM Dae-An;RYU Cheong-Ro
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.254-259
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    • 2001
  • In order to make clear the resistance of plane nettings u,sed widely in constructing net cages, the resistance R taken by $R=kSU^2$, where S was the wall area of nettings, U the flow velocity, and k the resistance coefficient, was measured in a circulating water channel by using nylon Raschel nettings and PE trawler-knotted nettings coated with anti-fouling paint or not and then the properties of coefficient k were investigated. The mesh size L and the angle $\phi$ between two adjacent bars was given by the function of Reynolds number ${\lambda}U/v$ in the region of ${\lambda}U/v<180$, i. e., $$k=350(\frac{\lambda U}{v})^{-0.25}$$.where $\lambda$ was the representative size of nettings expressed as $$\lambda=\frac{{\pi}d^2}{2L\;sin\;2{\phi}}$$On the other hand, the coefficient k was almost fixed between 92 and 102 ($kg{\cdot}s^2/m^4$) in the region of ${\lambda}U/v{\geq}180$ and varied according to the ratio $S_n/S$ of the total area $S_n$ of nettings projected to the plane perpendicular to the water flow to the wall area S of nettings, i.e., it was given by $$k=98.6(\frac{S_n}{S})^{1.19}$$ regardless of the coating of paint.

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Health Condition Assessment Using the Riparian Vegetation Index and Vegetation Analysis of Geumgang mainstream and Mihocheon (수변식생지수를 이용한 금강본류와 미호천의 건강성 평가 및 식생분석)

  • Lee, Seung-Yeon;Jang, Rae-Ha;Han, Young-Sub;Jung, Young-Ho;Lee, Soo-In;Lee, Eung-Pill;You, Young-Han
    • Korean Journal of Environment and Ecology
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    • v.32 no.1
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    • pp.105-117
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    • 2018
  • This study conducted health assessment and multivariate vegetation analysis using the riparian vegetation index in 30 sites of the Geumgang mainstream and Mihocheon to obtain practical data on the river management of the Geumgang. The result showed that the number of plant communities was 54. The flora was 75 families, 185 genera, 243 species, 2 subspecies, 21 varieties, 2 varieties, and 268 taxa. The riparian vegetation index was 38.3 (3.3; G-D1 ~ 66.7; G-U2, G-U4, and G-M3), and the health of the rivers in this area was evaluated as normal (grade C). The health of rivers was the highest in the upper stream of Geumgang mainstream and lowest in the downstream of Geumgang mainstream. The relationship between riparian vegetation index and chlorophyll-a content was low. The riparian vegetation was divided into five groups of Digitaria ciliaris colony group, Salix gracilistyla colony group, Erigeron annuus colony group, the group dominated by Humulus japonicus, Salix koreensis, Miscanthus sacchariflorus, and Phragmites japonica colonies, and the group dominated by Conyza canadensis and Echinochloa crusgalli var. echinata colonies. They had the similar health conditions. The CCA analysis showed that the environmental factors affecting the distribution of vegetation were physical factors such as vegetation area, artificial structure area, waterway area, branch width, channel width, and bank height and the biological factors such as the number of species. As such, it is necessary to maintain the health condition through continuous monitoring where the health condition is high and to apply active measures such as ecological restoration where the health condition is low.

A Case Study on High and Low Performance Areas for Family Planning (가족계획 우수.부진지역 사례연구)

  • 홍성열;김태일
    • Korea journal of population studies
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    • v.4 no.1
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    • pp.105-130
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    • 1981
  • This study was conducted to compare the characteristics of high performane areas for family planning with that of low performance areas and to find factors which strongly affected contraceptive practice behavior. For the study, eight areas were selected from 274 rural family planning canvassing areas of Korean Population Policy and Program Evaluation Study, which was an action study operated in all areas of Cheju Island from July 1, 1976 until December 31,1979. As a first step of the action study, Cheju Island was devided up 318 family planning canvasser areas Each area was consisted of 200 households in rural district and 300 households in urhan one Duriog the period of project, each canvassing area had been managed by a female family planning canvasser, selected by director of health center considering several individual conditions needed for family planning activities Basic activities of canvassers were to counsell all the eligihie couples in own charged area about family planning methods and also to distribute contraceptives such as condoms and oral pills. In case couples desire to accept sterilization including vasectomy and tubal-ligation, the canvassers played a linking role connecting potential client with family planning field workers. Canvassng areas shows significant differentce in performance for family planning, nevertheless they are supposed to have almost the same conditions regarding family planning distribution channel. Because the purpose of the Cheju project was to eliminate all the problems that existed in governmental distribution system, that is to remove geographic, economic, cognitive and administrative barriers Accumulated performances of family planning methods accepted by residents in each area were calculated by eligible women aged 14-49. And then canvassing areas were ranked according to performance score. Consequently, 4 areas in extremely high and low family planning performance areas were selected respectively. Major results were obtained by comparing characteristics of high performance area with that of low performance areas, which are as follows: 1. The mean number of living children was about the same both in high and low performance areas for family planning. But respondents' mean age (38.5) in high performance areas was higher than that (37.0) in low performance areas 2. Respondents' perception in the expectant educational level of others' children in high performance areas was higher than that in low performance areas, although respondents educational level, monthly expenditure and ratio of children in high school and above was not different. 3. Ratio of ownerships of TV and newspaper in high performance areas was highen than that in low performance areas 4. The duration of canvasser' charge in high performance areas was longer than that of low performance areas, showing the fact that canvassers didn't move cut in high performance areas 5. In high performance areas, canvassers' houses were relatively located in the center part of the village. And so villagers resided in near distances from the anvasser's house 6. 4H clubs' activities in high performance areas were more active than those in low performance areas Therefore it was assumed that cohesiveness of community in high performance areas were stronger than that in low areas. 7. Canvassers' family planning practice rate was higher than that in low performance areas, and also canvassers' human relationship was more sociable than that of canvassers in low performance areas. 8. Fourteen variables which showed relatively high significance level in $X^2$ and F test were selected as independent variables for stepwise regression analysis. According to the results of regression analysis. five of 14 variables-distributors education level ($R^2$=.4439), duration of distributor's charge ($R^2$=.6166), 4H club activities ($R^2$=.6697), canvasser's contraceptive practice ($R^2$=.7377) and location of distributions house ($R^2$=.8010) explained 80.1 percent of total variance.

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Case study on the lake-land combined seismic survey for underground LPG storage construction (LPG 지하저장기지 건설을 위한 수륙혼합 탄성파탐사 사례)

  • Cha Seong-Soo;Park Keun-Pil;Lee Ho-Young;Lee Hee-Il;Kim Ho-Young
    • 한국지구물리탐사학회:학술대회논문집
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    • 2002.09a
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    • pp.101-125
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    • 2002
  • A lake seismic survey was carried out to investigate possible geohazards for construction of the underground LPG storage at Namyang Lake. The proposed survey site has a land-lake combined geography and furthermore water depth of the lake is shallow. Therefore, various seismic methods such as marine single channel high resolution seismic reflection survey, sonobuoy refraction survey, land refraction survey and land-lake combined refraction survey were applied. Total survey amounts are 34 line-km of high resolution lake seismic survey, 14 lines of sonobuoy refraction survey, 890 m of land refraction survey and 8 lines of land-lake combined refraction survey. During the reflection survey, there were severe water reverberations from the lake bottom obscured subsurface profiling. These strong multiple events appeared in most of the survey area except the northern and southern area near the embankment where seems to be accumulated mainly mud dominated depositions. The sonobuoy refraction profiles also showed the same Phenomena as those of reflection survey. Meanwhile the results of the land-lake combined refraction survey showed relatively better qualities. However, the land refraction survey did not so due to low velocity soil layer and electrical noise. Summarized results from the lake seismic survey are that acoustic basement with relatively flat pattern appeared 30m below water level and showed three types of bedrock such as fresh, moderately weathered and weathered type. According to the results of the combined refraction survey, a velocity distribution pattern of the lake bottom shows three types of seismic velocity zone such as >4.5 km/s, 4.5-4.0km/s and <4.0km/s. The major fault lineament in the area showed NW-SE trend which was different from the Landsat image interpretation. A drilling was confirmed estimated faults by seismic survey.

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Effects of Ginsenosides on Glucose Uptake and Insulin Secretion

  • Park, Min-Woo;Shin, Eun-Jung;Ko, Sung-Kwon;Chung, Sung-Hyun
    • Proceedings of the Ginseng society Conference
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    • 2007.05a
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    • pp.23-24
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    • 2007
  • Purpose: 인삼이 항당뇨 활성을 가진다는 연구가 많은 연구자들에 의해 진행되었고, 이는 인삼의 구성 성분 중 ginsenoside에 기인한다는 보고가 있다. 본 연구는 ginsenoside의 항당뇨 작용기전을 in vitro에서 알아보고자 3T3-L1 지방세포에서 glucose uptake와 췌장 베타세포인 HIT-T15 세포에서 insulin 분비 효과를 확인하였다. 이를 위하여 인삼을 식초로 처리한 긴삼의 70% MeOH 분획으로부터 protopanaxadiol 계인 ginsenoside $Rb_2$, $Rg_3$ 그리고 protopanaxtriol 계인 $Rg_2$를 분리하여 본 실험에 사용하였다. Method: Ginsenoside $Rb_2$, $Rg_2$, $Rg_3$가 지방 세포에서 glucose uptake에 미치는 효과를 확인하기 위하여 3T3-L1 세포를 DMEM (Dulbecco's Modified Eagle's Medium) 배지에서 분화 유도시켰으며 3T3-L1 preadipocyte가 80% 정도 자라면 분화 유도 배지 (5% fetal bovine serum (FBS), 0.5 mM isobutylmethylxanthine (IBMX), 1 mM dexamethasone 그리고 $10{\mu}g/ml$ insulin가 포함된 DMEM)로 4일, $10{\mu}g/ml$ insulin가 포함된 DMEM으로 2일, FBS만 포함된 DMEM으로 2일 배양하여 총 8일 동안 분화를 유도하였다. 분화 유도된 3T3-L1 adipocytes 에 각각 $Rb_2$, $Rg_2$, $Rg_3$$20{\mu}M$로 처리하여 16시간 배양하여 low glucose DMEM에서 3시간 배양한 후에 $37^{\circ}C$에서 insulin 10 ng/ml 과 각각 $Rb_2$, $Rg_2$, $Rg_3$가 포함된 Krebs Ringer Hepes buffer(KRP buffer)에서 20분간 배양하였다. 2-deoxy-D-[$^3H$]-glucose를 넣고 10분 후에 차가운 PBS로 반응을 종결시켜 lysis buffer로 cell을 모은 후 scintillation counter를 이용하여 glucose를 측정하였다. Insulin 분비 효과는 HIT-T15 세포와 일차 배양한 흰쥐 소도세포(islets)를 사용하여 확인하였다. HIT-T15 세포는 24 well plate에 well 당 $2{\times}10^5$ 개씩 분주하여 24시간 동안 배양한 후 시료를 처리하였으며 소도 세포는 Sprague-Dawley rat의 췌장에 collagenase가 포함된 Hanks' Balanced Salt Solution(HBSS)을 주입하여 분리하고 islets을 얻었다. 분리한 소도세포를 $1{\sim}2$일 동안 배양하여 $Rb_2$, $Rg_2$, $Rg_3$가 각각 $20{\mu}M$의 농도로 첨가된 insulin 측정용 buffer인 Krebs-Ringer buffer (KRB+0.3% BSA, KRBB)에 $37^{\circ}C$에서 1시간 incubation 시킨 후 배양액으로 분비된 인슐린의 양을 측정하였다. 한편 ginsenoside의 인슐린 분비 촉진 기전을 알아보기 위한 실험에서는 ATP-sensitive $K^+$ channel opener인 diazoxide (0.5 mM)가 ginsenoside에 의해 촉진된 인슐린 분비를 억제하는지 살펴보았다. Result: glucose uptake assay 에서는 $Rg_2$가 가장 크게 glucose uptake를 증가시켰고 $Rb_2$, $Rg_3$는 그 활성이 크지 않았다. 한편 Insulin 분비 효과는 diol계인 $Rg_3$에서 용량 의존적으로 인슐린의 분비를 촉진시켰으며 $20{\mu}M$ 농도에서 대조군과 비교해 1.5배 이상의 분비 촉진 효과를 보였고 triol계인 $Rg_2$ 에서는 이러한 효과가 나타나지 않았다. $Rg_3$의 인슐린 분비 촉진 기전을 0.5 mM 의 diazoxide를 이용하여 확인한 결과 $Rg_3$에 의해 촉진된 인슐린 분비를 감소시켰다. 이로 미루어보아 $Rg_3$의 인슐린 분비 촉진 기전은 ATP-sensitive $K^+$ 채널의 봉쇄에 의한 것임을 확인할 수 있었다.

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A Comparative Study of the Oriental and the Occidental Medical Literature on the Etiologies & Treatments for Palmoplantar Hyperhidrosis (수족한(手足汗)의 원인(原因)과 치료법(治療法)에 대한 동(東).서의학적(西醫學的) 고찰(考察))

  • Ko, Young-Chul;Shin, Jo-Young
    • The Journal of Internal Korean Medicine
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    • v.18 no.2
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    • pp.268-295
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    • 1997
  • Sweating is natural phenomenon necessary for the regulation of an individual's body-temperature. The secretion of sweat is mediated by a portion of our vegetative nervous system(the sympathetic nervous system). In some people, this system is working at a very high activity level, far higher than needed to keep a constant temperature. This condition is referred to as hyperhidrosis. Especially excessive sweating of the hands and the feet is palmoplantar hyperhidrosis or volar hyperhidrosis. This is by far the most distressing condition. It was founded that the first important cause of this was emotional factor. The hands are much more exposed in social and prefessional activities than any other part of our body. Many individuals with palmoplantar hyperhidrosis are limited in their choice of proffession, because unable to manipulate materials sensitive to humidity or reluctant to shake hands; some patients arrive to the point to avoid social contact. The occidental medical treatments for palmoplantar hyperhidrosis include application of topical agents(chemical antiperspirants such as aluminum chloride), iontophoresis(treatment with electrical current), or surgery(thoracic sympathectomy). It was reported that the most effective treatment was thoracic sympathectomy. So this study was started to find the easy and effective oriental medical treatments against the occidental medical treatments through the oriental medical literature. The occidental medical idea for palmoplantar hyperhidrosis is only limited in neurologic system, so surgery is the best treatment. But the oriental medical idea for palmoplantar hyperhidrosis is much wider, so the oriental medical causes and treatments for this are able to be veriety. And the oriental medical teatment is freely in treating the patients of palmoplantar hyperhidrosis, because entire idea including pulse, facial color, mental condition, constitution and other symptom exists in the oriental medicine. The results of a bibliographic study of causes and treatments for palmoplantar are as follows; 1. The main causes of pa1moplantar hyperhidrosis are heat in the stomach, damp-heat in the spleen and the stomach, insufficiency of the spleen-qi and the stomach-qi, deficiency of the spleen-yin and the stomach-yin, and the others are the stomach-cold syndrome, stasis of blood and dyspepsia in the stomach, disorder of the liver-qi, deficiency of the heart-yin and the kidney-yin, deficiency of the heart-yang and the kidney-yang, stagnated heat in the liver and the spleen, the lung channel-heat etc. 2. The main methods of medical treatments for palmoplantar hyperhidrosis are clearing out the stomach-heat, eliminating dampness and heat in the spleen and the stomach, invigorating the spleen-qi and the stomach-qi, reinforcing the spleen-yin and the stomach-yin, warming the stomach, relaxing the liver and alleviating of mental depression and tonifying the heart and the kidney etc. 3. The main prescriptions of palmoplantar hyperhidrosis are Taesihotang, Palmultang-kakam, Samyeongbaechusan, Chongbisan, Sasammaekmundongtang, the others are Leejungtang, Hwangkikonjungtang, Seungkitang, Boyumtang, Baekhotang, Chongsimyonjayum, Moyrosan, etc. 4. Local medicine for external use are liquid after boiling alum in water for about 1 or 2 hours, liquid after boiling alum and pueraria root in water and liquid after boiling stragalus root, pueraria root, ledebouriella root and schizonepeta in water, etc. 5. The methods of acupuncture therapy include invigorating Bokyru, Yumkuk and purgating Hapkouk, or invigorating Bokyru, Kihae and purgating Hapkouk, or steadying Hapkouk, Nokung.

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Fluid-mud deposits in the Early Cretaceous McMurray Formation, Alberta, Canada (캐나다 앨버타주 전기 백악기 맥머레이층의 유성이토 퇴적층)

  • Oh, Juhyeon;Jo, Hyung Rae
    • Journal of the Geological Society of Korea
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    • v.54 no.5
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    • pp.477-488
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    • 2018
  • Fluid muds commonly occur in estuarine environments, but their ancient examples have rarely been studied in terms of depositional characteristics and processes. Cores of estuarine channel deposits of the Early Cretaceous McMurray Formation, Alberta, Canada show various mudstone layers that possess depositional characteristics of high clay-concentration flows. These mudstone layers are examined in detail through microscopic observation of thin sections and classified into three microfacies (<1 to 25 mm thick) on the basis of sedimentary texture and structures. Structureless mudstone (Microfacies 1) consists mainly of clay particles and contains randomly dispersed coarser grains (coarse silt to fine sand). This microfacies is interpreted as being deposited by cohesive mud flows, i.e., fluid muds, which possessed sufficient strength to support suspended coarser grains (quasi-laminar plug flow). Silt-streaked mudstone (Microfacies 2) mainly comprises mudstone with dispersed coarse grains and includes very thin, discontinuous silt streaks of coarse-silt to very-fine-sand grains. The texture similar to Microfacies 1 indicates that Microfacies 2 was also deposited by cohesive fluid muds. The silt streaks are, however, suggestive of the presence of intermittent weak turbulence under the plug (upper transitional plug flow). Heterolithic laminated mudstone (Microfacies 3) is characterized by alternation of relatively thick silt laminae and much thinner clay laminae. It is either parallel-laminated or low-angle cross-laminated, occasionally showing low-amplitude ripple forms. The heterolithic laminae are interpreted as the results of shear sorting in the basal turbulent zone under a cohesive plug. They may represent low-amplitude bed-waves formed under lower transitional plug flows. These three microfacies reflect a range of flow phases of fluid muds, which change with flow velocities and suspended mud concentrations. The results of this study provide important knowledge to recognize fluid-mud deposits in ancient sequences and to better understand depositional processes of mudstones.