• Title/Summary/Keyword: peak function

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The expression patterns of RANKL and OPG in murine tooth eruption (치아발육시기에서의 RANKL 및 OPG의 발현 양상)

  • Hwang, Kyung-Mun;Kim, Eun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun;Kim, Hyun-Jung
    • Journal of the korean academy of Pediatric Dentistry
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    • v.33 no.2
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    • pp.290-303
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    • 2006
  • Tooth eruption is a complex and tightly regulated process that involves cells of the tooth organ and the surrounding alveolus. Osteoclast precursors must be recruited into the dental follicle prior to the onset of eruption. This function of dental follicle may be regarded as the ability of bone remodeling characterized by the interaction of osteoclasts and osteoblasts. This is because tooth eruption is a localized event in which many of the genes required for eruption are expressed in the dental follicle. RANKL is a membrane-bound protein that is a member of the TNF ligand family. which is present on bone marrow stromal cells and osteoblasts, and induces osteoclast formation and activation from precursor cell. The biologic effect of RANKL is inhibited by OPG and, in bone, the relative ratio of RANKL and OPG modulates osteoclastogenesis. To evaluate the roles of RANKL and OPG in tooth eruption and the relations with the expression pattern of Runx2, in situ hybridization was performed with mandibles of mice at postnatal stage 1, 3, 5, 7, 9 and 11. mRNA of RANKL, OPG, and Runx2 are expressed in dental follicle and surrounding tissue from P1 to 11. To determine the sites of osteoclastic activity during tooth eruption, mandibles were dissected. Peak osteoclastic activity in alveolar bone along the occlusal and basal regions was observed from P5 to 9, with osteoclasts in these regions being large and strongly TRAP-positive The specific spatio-temporal expression patterns of RANKL, OPG, and Runx2 in our study suggest that tooth eruption could be progressed through the interactions of molecular signaling among dental follicle, dental organ and alveolar bone, furthermore it means that dental follicle is quite important in tooth eruption In addition, it indicates that these genes (RANKL, OPG, and Runx2) play critical roles in tooth eruption.

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EFFECT OF NERVE GROWTH FACTOR GENE INJECTION ON THE NERVE REGENERATION IN RAT LINGUAL NERVE CRUSH-INJURY MODEL (백서 설신경 압박손상모델에서 신경성장인자 유전자 주입이 신경재생에 미치는 영향)

  • Gao, En-Feng;Chung, Hun-Jong;Ahn, Kang-Min;Kim, Soung-Min;Kim, Yun-Hee;Jahng, Jeong-Won;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.28 no.5
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    • pp.375-395
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    • 2006
  • Purpose: Lingual nerve (LN) damage may be caused by either tumor resection or injury such as wisdom tooth extraction, Although autologous nerve graft is sometimes used to repair the damaged nerve, it has the disadvantage of necessity of another operation for nerve harvesting. Moreover, the results of nerve grafting is not satisfactory. The nerve growth factor (NGF) is well-known to play a critical role in peripheral nerve regeneration and its local delivery to the injured nerve has been continuously tried to enhance nerve regeneration. However, its application has limitations like repeated administration due to short half life of 30 minutes and an in vivo delivery model must allow for direct and local delivery. The aim of this study was to construct a well-functioning $rhNGF-{\beta}$ adenovirus for the ultimate development of improved method to promote peripheral nerve regeneration with enhanced and extended secretion of hNGF from the injured nerve by injecting $rhNGF-{\beta}$ gene directly into crush-injured LN in rat model. Materials and Methods: $hNGF-{\beta}$ gene was prepared from fetal brain cDNA library and cloned into E1/E3 deleted adenoviral vector which contains green fluorescence protein (GFP) gene as a reporter. After large scale production and purification of $rhNGF-{\beta}$ adenovirus, transfection efficiency and its expression at various cells (primary cultured Schwann cells, HEK293 cells, Schwann cell lines, NIH3T3 and CRH cells) were evaluated by fluorescent microscopy, RT-PCR, ELISA, immunocytochemistry. Furthermore, the function of rhNGF-beta, which was secreted from various cells infected with $rhNGF-{\beta}$ adenovirus, was evaluated using neuritogenesis of PC-12 cells. For in vivo evaluation of efficacy of $rhNGF-{\beta}$ adenovirus, the LNs of 8-week old rats were exposed and crush-injured with a small hemostat for 10 seconds. After the injury, $rhNGF-{\beta}$ adenovirus($2{\mu}l,\;1.5{\times}10^{11}pfu$) or saline was administered into the crushed site in the experimental (n=24) and the control group (n=24), respectively. Sham operation of another group of rats (n=9) was performed without administration of either saline or adenovirus. The taste recovery and the change of fungiform papilla were studied at 1, 2, 3 and 4 weeks. Each of the 6 animals was tested with different solutions (0.1M NaCl, 0.1M sucrose, 0.01M QHCl, or 0.01M HCl) by two-bottle test paradigm and the number of papilla was counted using SEM picture of tongue dorsum. LN was explored at the same interval as taste study and evaluated electro-physiologically (peak voltage and nerve conduction velocity) and histomorphometrically (axon count, myelin thickness). Results: The recombinant adenovirus vector carrying $rhNGF-{\beta}$ was constructed and confirmed by restriction endonuclease analysis and DNA sequence analysis. GFP expression was observed in 90% of $rhNGF-{\beta}$ adenovirus infected cells compared with uninfected cells. Total mRNA isolated from $rhNGF-{\beta}$ adenovirus infected cells showed strong RT-PCR band, however uninfected or LacZ recombinant adenovirus infected cells did not. NGF quantification by ELISA showed a maximal release of $18865.4{\pm}310.9pg/ml$ NGF at the 4th day and stably continued till 14 days by $rhNGF-{\beta}$ adenovirus infected Schwann cells. PC-12 cells exposed to media with $rhNGF-{\beta}$ adenovirus infected Schwann cell revealed at the same level of neurite-extension as the commercial NGF did. $rhNGF-{\beta}$ adenovirus injected experimental groups in comparison to the control group exhibited different taste preference ratio. Salty, sweet and sour taste preference ratio were significantly different after 2 weeks from the beginning of the experiment, which were similar to the sham group, but not to the control group.

The Influence of the Landscaping Shade Materials' Porosity on the Mean Radiant Temperature(MRT) of Summer Outdoors (조경용 차양 재료의 공극률이 하절기 옥외공간 평균복사온도에 미치는 영향)

  • Lee, Chun-Seok;Ryu, Nam-Hyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.2
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    • pp.60-67
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    • 2017
  • The purpose of this study was to evaluate the influence of landscaping shade materials' porosity on the Mean Radiant Temperature (MRT) of summer outdoors. The MRTs were measured under seven different types of black membranes with holes of 8mm diameter at different intervals applied on the top of wooden boxes, and compared with those of four additional control plots with or without shade and lateral boxes. The applied porosities were 0.5, 1, 2, 4, 8, 16%, and 32%, and three groups of three shades were compared sequentially from August 13 to September 8, 2016. The MRTs under the shade without lateral block, no shade with lateral block, and shade with lateral block were $33.08^{\circ}C$, $45.80^{\circ}C$, and $42.3^{\circ}C$, respectively, while that of no-shaded no-lateral screen was $44.26^{\circ}C$, based on records from 11:00 AM to 3:00 PM on the days with a peak globe temperature higher than $30^{\circ}C$. An ANCOVA analysis showed that the MRTs under the shades with 0.5, 1, 2, 4, 8, 16%, and 32% porosities were calculated as 43.40, 43.10, 41.49, 40.43, 39.61, $37.91^{\circ}C$, and $38.12^{\circ}C$, respectively, while that in the no shaded control box was $45.8^{\circ}C$. The curve fitted between MRTs and the porosity showed a U-shaped quadratic function with the minimum MRT at 16% practically or 22.5% statistically.

Production Increase of Milk in Dairy Cow by Metabolic Profile Test (대사판정시험을 이용한 젖소의 우유증산)

  • Lee Chang-Woo;Kim Bonn-Won;Ra Jeong-Chan;Shin Sang-Tae;Kim Doo;Kim Jong-Taik;Hong Soon-Il
    • Journal of Veterinary Clinics
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    • v.10 no.1
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    • pp.65-94
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    • 1993
  • This study examined metabolic profiles of 1349 Holstein cows from 91 commercial herds. Thirteen parameters which are consisted of twelve blood components and body condition score were examined and their mean values. standard deviations and standard limits, which are 80% confidential limits, in each lactational stage were reported. The variations of each parameter affected by season, individual milk yield, adjusted corrected milk yield of herd. and lactation number were also reported. A model of metabolic profile test applicable to this country where the average number of cows in a herd is small as to be fifteen is designed. Metabolic profiles as reflected in each parameter were discussed in relation to adequacy of dietary intake for production, milk production, reproductive performance, and diseases, and the possible measure to improve productivity of dairy cows were proposed. Much of the variation in parameters was due to differences between herds, and less to differences between seasons, differences between individual milk yield, and differences between lactational stages. As the average herd size in this country is small, it is believed that all the cows in a herd must be sampled, and the individual result of each parameter was compared with the standard limit for each lactational stage, and the percentage of cows which are outside the standard limits in a herd was calculated to use as a criteria for evaluation of the herd. Data outside the 99% confidential limits were to be deleted at first, but when the trends of the data outside the 99% confidential limits are same as the trends of the data within 99% confidential limits, the deleted data must be reviewed again, otherwise some important informations would be missed. The mean concentration of blood urea nitrogen in this study was much higher than that was reported in England, U.S.A. and Japan, and it was similar to the upper limits reported in England, U.S.A. and Japan. So it was thought that the concentration of blood urea nitrogen is improper as a criteria for protein intake. The increase of serum total protein cocentration beyond standard limits was due to increase of serum globulin concentration in most of the cows. The correlation coefficient between serum and protein and serum globulin concentration was 0.83. Serum globulin concentration was negatively related to adjusted corrected milk of herd. Serum albumin, calcium and magnessium concentrations were negatively related to adjusted corrected milk of herd, which indicate that high-producing individual or high-producing herd have not taken sufficient protein/amino acids, calcium and magnessium. Packed cell volume was negatively related to adjusted corrected milk of the herd, and the trend was same In each lactational stage. The correlation coefficient between serum and packed cell volume was 0.16 and the correlation was very weak. Blood glucose concentration was lowest in early lactational stage, which indicates negative energy balance in early lactational stage. Blood glucose concentration was negatively related to adjusted corrected milk of herd from peak to late lactational stage, which indicates negative energy balance during the period in high-producing individuals or high-producing herds. Correlation coefficient between serum aspartate aminotransferase activity and serum ${\gamma}$-glutamyltransferase activity was 0.41, and this indicates that serum ${\gamma}$-glutamyltransferase should be included as a parameter of metabolic profile test to evaluate liver function. Body condition score of dairy cows in this country was lower than that of Japan in every lactational stages, and the magnitude of increase in body condition score during middle and late lactational stages was small. Metabolic profile can not be evaluated with solely nutritional intake. When an individual or large percentage of cows in a herd have adnormal values In parameters of metabolic profile test, veterinary clinician and nutritionist should cooperate so as to diagnose diseases and to calculate the e of no운ents simultaneously.

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The Correlations of Parameters Using Contrast Enhanced Ultrasonography in the Evaluation of Prostate Cancer Angiogenesis (전립선암쥐모형의 신생혈관생성의 평가를 위해 시행된 역동적 조영 증강 초음파에서 얻은 변수간의 상관성연구)

  • Hwang, Sung Il;Lee, Hak Jong;Kim, Kil Joong;Chung, Jin-haeng;Jung, Hyun Sook;Jeon, Jong June
    • Ultrasonography
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    • v.32 no.2
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    • pp.132-142
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    • 2013
  • Purpose: The purpose of this study is to investigate the correlations of various kinetic parameters derived from the time intensity curve in a xenograft mouse model injected with a prostate cancer model (PC-3 and LNCaP) using an ultrasound contrast agent with histopathologic parameters. Materials and Methods: Twenty nude mice were injected with human prostate cancer cells (15 PC-3 and five LNCaP) on their hind limbs. A bolus of $500{\mu}L$ ($1{\times}10^8$ microbubbles) of second-generation US contrast agent (SonoVue) was injected into the retroorbital vein. The region of interest was drawn over the entire tumor. The time intensity curve was acquired and then fitted to a gamma variate function. The maximal intensity (A), time to peak (Tp), maximal wash-in rate (washin), washout rate (washout), area under the curve up to 50 sec ($AUC_{50}$), area under the ascending slope ($AUC_{in}$), and area under the descending slope ($AUC_{out}$) were derived from the parameters of the gamma variate fit. Immunohistochemical staining for VEGF and CD31 was performed. Tumor volume, the area percentage of VEGF stained in a field, and the count of CD31 (microvessel density, MVD) positive vessels showed correlation with the parameters from the time intensity curve. Results: No significant differences were observed between the kinetic and histopathological parameters from each group. MVD showed positive correlation with A (r=0.625, p=0.003), washin (r=0.462, p=0.040), $AUC_{50}$ (r=0.604, p=0.005), and $AUC_{out}$ (r=0.587, p=0.007). Positive correlations were also observed between tumor volume and $AUC_{50}$ (r=0.481, p=0.032), washin (r=0.662, p=0.001), and $AUC_{out}$ (r=0.547, p=0.012). Washout showed negative correlations with MVD (r=-0.454, p=0.044) and tumor volume (r=-0.464, p=0.039). The area percentage of VEGF did not show any correlation with calculated data from the curve. Conclusion: MVD showed correlations with several of the kinetic parameters. CEUS has the potential for prediction of tumor vascularity in a prostate cancer animal model.

Effect of Accelerated Rehabilitation with Anti-Gravity Treadmill Exercise on Ankle Joint Function After Surgery of Modified Brostrom Operation in Chronic Ankle Instability Patients (변형된 Brostrom 수술 후, Anti-gravity treadmill 가속재활운동이 만성발목불안정성 환자의 발목기능 회복에 미치는 영향)

  • Choi, In-Hyuk;Lee, Jang-Kyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.7
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    • pp.228-235
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    • 2019
  • The purpose of this study was to investigate the effect of 6 weeks' accelerated rehabilitation with anti-gravity treadmill exercise on VAS, ROM, isokinetic myofunction, and dynamic stability after surgery of modified brostrom operation in chronic ankle instability patients. The subjects of this study were 12 chronic ankle instability patients who underwent modified Brostrom operation(MBO) by the same doctor. 6 weeks' accelerated rehabilitation program is scheduled to perform for 60min, everyday, and also anti-gravity program performed for 15~30min, everyday. The visual analog scale(VSA) and significantly decreased(p<.001) and ROM in all of dorsal flexion, plantar flexion, inversion and eversion significantly increased(p<.05) after 6 weeks' accelerated rehabilitation with anti-gravity treadmill exercise. Both inversion and eversion peak torque at $60^{\circ}/sec$(p<.001, p<.01) and at $180^{\circ}/sec$(p<.001) significantly increased after 6 weeks' accelerated rehabilitation with anti-gravity treadmill exercise respectively. In muscle defect, although inversion(p<.01) and eversion(p<.001) at $60^{\circ}/sec$ and inversion(p<.01) at $180^{\circ}/sec$ significantly decreased, eversion at $180^{\circ}/sec$ tended to decrease but did not change significantly after 6 weeks' accelerated rehabilitation with anti-gravity treadmill exercise. The dynamic stability significantly increased after 6 weeks' accelerated rehabilitation with anti-gravity treadmill exercise(p<.001). These results suggest that 6 weeks' accelerated rehabilitation with anti-gravity treadmill exercise has positive effect of VAS, ROM, isokinetic myofunction, and dynamic stability after surgery of modified brostrom operation in chronic ankle instability patients. Therefore, we consider that the accelerated rehabilitation with anti-gravity treadmill exercise, which is safely and fast method, has effect on more faster recovery of ankle stability, play ground and normal daily activities.

A Study on the Meaning and Mount Effect of Twelve Peaks of Musan in Yongho Garden, Jinju (진주 용호정원(龍虎庭園) 무산십이봉의 경관의미와 축산효과)

  • Lee, Hyun-Woo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.4
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    • pp.27-39
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    • 2011
  • The study on Musan twelve peaks of Yongho garden in Jinju, Gyeongnam was anticipated to provide data and implication for reproducing similar spaces and modern changes in terms of design factor since it is the prototype of traditional mount for overcoming monotonous geographical features and intriguing changes and interests. The study analyzed and interpreted the symbolism of twelve peaks, principles of space composition and function and effect of visual construction that were pursued by the builder in terms of landscape view, which results are as following. The center of Yongho garden, Yonghoji(龍虎池) is a typical man-made pond for a supportive feng shui feature. It is a supporting equipment to complete the state of feng shui, and the result of strengthening the completion through the connection with the dragon-related name of the place. The shape of Musan twelve peaks looks like an oval form of Geumseongsan(金星山), 2~3.5m in height and 6~12m in diameter. Peaks are estimated as 1.5~3.7m(2.4m in average) in height, $35{\sim}138m^2$($73.4m^2$ in average) in area, and $30.7{\sim}115.0m^3$($62.5m^3$ in average) in volume. Given that Yonghojeong(龍虎亭), Soseon(小船), the site of main building and Yongsanjae(龍山齋) stand in line, Yonghoji was presumed as the state of enlightenment through ascribing the meaning to virtue and secularity. For the intention of realizing Musan twelve peaks, the builder probably had mounted twelve peaks forming the body of dragons with crossing the point corresponding to a head of tiger, and located Musan twelve peaks and Yonghojeong with a representation of dragons holding Cintamani rising into the sky in the center. The middle area near Musan twelve peaks surrounded by peaks like Geumseongsan running north and south shows a multi-structure of multilayer, maintaining the similarity centering on Yonghoji. It is considered the intention of mount planned at the time of Musan twelve peaks construction, caused by similar form harmony. Internalization of progressive realization through concealment and exposure, enframement effect and spatial order like prospect-refuge theory in the mount of Musan twelve peaks is considered the reflection of the intention to increase depth of the view and expectancy through the various degree of exposure and surroundings of each peak and the colorful combination of viewing and shutting. The "closed view" by Musan twelve peaks creates interesting, vivid and attractive recognition of the view, which is more effective in bringing depth of the view and interests in terms of the geographical design, particularly the area around Yonghoji. Moreover, it was identified that the combination of peaks can be formed resulted from the view configuration concerning the location through multilayer effect reveals an island through the other one when viewed from Yonghojeong.

Conjunction of Consciousness and The Unconscious·Individuation and Circumambulation of The Psyche: Focusing on the Hexagram Bi, Pi (比) and Hexagram Gon, Kun (坤) (의식과 무의식의 통합 및 개성화와 정신의 순환: 수지비괘(일양오음괘)와 중지곤괘를 중심으로)

  • Hyeon Gu Lee
    • Sim-seong Yeon-gu
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    • v.38 no.1
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    • pp.1-44
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    • 2023
  • Hexagram Bi (比 ䷇ 8) is one of the hexagrams comprised of one-unbroken line and five-broken lines. The hexagrams of one-unbroken and five-broken lines symbolize the relationship and dynamics between one yang-consciousness and the five-yin unconsciousness. The hexagram of one-unbroken line and five-broken lines has six different images depending on the position of the one unbroken line from the beginning line to the top line. In terms of psychology, this means that the position change of one yang line in relation to five yin lines may symbolize the function of consciousness which clarifies and determines the content of the psyche. In addition, the flow of psychic energy can be examined through the process of one unbroken line's movement. In other words, the psychic contents of the beginning line of hexagram Bok (復 ䷗ 24), which is the beginning of the hexagram of one-unbroken line and five-broken lines, proceed sequentially, and then arrive at the process of the last sixth, hexagram Bak (剝 ䷖ 23) through the fifth, the hexagram Bi (8). That is, it can be said that the content of the hexagram and the line determined according to the position of one unbroken line show a certain psychic flow. As a result, the first hexagram Bok (復 ䷗ 24), after recovering and starting newly, means the beginning of consciousness. After that the process of proceeding with the second, third, and fourth lines represents the flow of consciousness. And in the fifth place, the fifth line of hexagram Bi, it reaches its peak and is placed in the optimal state of consciousness because of its right and centered position at this hexagram Bi. Like nature, the psyche gradually enters the path of decline from the highest state, which leads to the last sixth, the top line of hexagram Bak. However, the top line of the hexagram Bak, where everything falls off, contains the content of starting again in its top line. It is the beginning line of hexagram Bok to inherit this. This means the circumambulation of the psyche that changes from a psychologically difficult state of depression to a stage of recovery. There is a stage that must be passed in this circulation process, and that is the hexagram Gon (坤 ䷁ 2). October(tenth month)'s hexagram Gon is placed between hexagram Bak, the ninth month of the lunar calendar, and hexagram Bok, the eleventh month of the lunar calendar. This represents that the flow of recovery must go through a maternal process of hexagram Gon. The retreat to the psychological uterus is inevitable in regenerating the psyche. This process flows from the hexagram Bak and through hexagram Gon to the hexagram Bok. At this situation the hexagram Gon acts the absolutely necessary role. In addition, the main body of the hexagrams of one-unbroken and five-broken lines, including the Bi hexagram, is also the Gon hexagram composed of six-broken lines. In other words, all six hexagrams of one-unbroken and five-broken lines have a certain relationship with the Gon hexagram, and it would be meaningful to look at the correlation between the unbroken lines of the hexagrams of one-unbroken and five-broken lines and the corresponding broken lines of the hexagram Gon. This can be said to be the dynamics of the maternal unconscious connected to the state of consciousness in six forms. Therefore, each hexagram of one-unbroken and five-broken lines symbolizes the expression of the integration the mother archetype with the consciousness. Revealing this well is the meaning of the hexagram of one-unbroken and five-broken lines. Its hexagram image consists of a combination of Gon (☷), which symbolizes the mother, and the thunder (☳) the eldest son, the water (☵) the middle son and the mountain (☶) the third son. As a result, the hexagram Bok (復 ䷗ 24), Sa (師 ䷆ 7), Gyeom (謙 ䷠ 15), Ye (豫 ䷏ 16), Bi (比 ䷇ 8) and Bak (剝 ䷖ 23) are sequentially created in the order of the unbroken line. This is symbolically the evolutionary process of consciousness. In this way, the hexagrams of one-unbroken and five-broken lines, which mean the conjunction of mother and son, represent the advancing relationship between the maternal unconscious and consciousness. In addition, the relationship with the mother according to the position of the son is related to the dynamics of mother archetype to the attitude of consciousness. The psychological meaning can be deduced from the flow of six lines of hexagrams of one-unbroken and five-broken lines. And the state in which the activation of the consciousness is at its peak is the fifth line of the hexagram Bi, and comparing it with the contents of the corresponding fifth line of hexagram Gon not only can find the state and meaning of the conjunction of consciousness and the maternal unconscious, but the entire flow can be compared to the individuation process.

Early Clinical Experience in Aortic Valve Replacement Using On-X$^{circledR}$Prosthetic Heart Valve (On-X$^{circledR}$ 기계판막을 이용한 대동맥판 치환술의 조기 임상 경험)

  • 안병희;전준경;류상완;최용선;김병표;홍성범;박종춘;김상형
    • Journal of Chest Surgery
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    • v.36 no.9
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    • pp.651-658
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    • 2003
  • Since the first implanted in September 1997, the use of On-X prosthetic heart valve has been increasing around in the world. This study was designed to assess the feasibility, safety, and the postoperative hemodynamics with this new valve in clinical setting. Material and Method: The current study was carried out on 52 patients undergoing aortic valve replacement with this prosthesis between April 1999 to August 2002 at Chonnam National University Hospital to evaluate the surgical results. 52% of the patients were male and the average age at implant was 50$\pm$13 years. The study followed the guidelines of the AATS/STS. Preoperatively, 32(61.5%) patients were in NYHA functional class III or IV and 2 patients had previous aortic valve surgery. Concomitant cardiac surgery was performed in 71.1%. The implanted valve sizes were 19 mm in 13 patients, 21 mm in 26, 23 mm in 10 and 25 mm in 3, respectively. Mean follow-up was 16.6$\pm$10.5 months (1∼39 months). Echocardiographic assessment was performed pre- and immediate postoperatively, as well as 3, 6, 12 months after surgery, evaluating pressure loss and regression of left ventricular hypertrophy. Result: Mean cardiopulmonary bypass time was 191$\pm$94.7 minutes with an aortic cross-clamp time of 142$\pm$51.7 minutes. There was no early and late mortality, Freedom from adverse events at 1 year in the study were as follows: thromboembolism, 95.6$\pm$6%; bleeding events, 90.2$\pm$4%; paravalvular leakage 92.3$\pm$4%; and overall valve-related morbidity at 1 year was 76.6$\pm$3%. There were no cases of valve thrombosis, prosthetic valve endocarditis and structural or non-structural failure. Left ventricular function at 12 months after surgery (EF=62.7$\pm$9.8%) revealed a statistically significant improvement compared to preoperative investigation (EF=55.8$\pm$15.9%, p=0.006). Left ventricular mass index was 247.3$\pm$122.3 g/$m^2$ on preoperative echocardiographic study, but regressed to 155.5$\pm$58.2 g/$m^2$ at postoperative 1 year (p=0.002). Over the follow-up period a further decrease of peak transvalvular gradients was observed in all patients: 62.5$\pm$38.0 mmHg on preoperative assessment, 18.2$\pm$6.8 mmHg at immediate postoperative period (p < 0.0001), 7.6$\pm$5.09 mmHg (p<0.0001) at 6 month, 18.0$\pm$10.8 mmHg (p<0.0001) at 1 year. Conclusion: The On-X prosthetic heart valve performs satisfactorily in the first 1 year period. Clinical outcome by examining NYHA functional classification revealed especially good results. Effective regression of left ventricular hypertrophy and statistically significant decrease of transvalvular gradient were observed over the first year, but longer-term follow-up of this patient group is needed to establish the expected rates for late valve-related events as well as the long-term clinical efficacy of this valve.

Relationships on Magnitude and Frequency of Freshwater Discharge and Rainfall in the Altered Yeongsan Estuary (영산강 하구의 방류와 강우의 규모 및 빈도 상관성 분석)

  • Rhew, Ho-Sang;Lee, Guan-Hong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.16 no.4
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    • pp.223-237
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    • 2011
  • The intermittent freshwater discharge has an critical influence upon the biophysical environments and the ecosystems of the Yeongsan Estuary where the estuary dam altered the continuous mixing of saltwater and freshwater. Though freshwater discharge is controlled by human, the extreme events are mainly driven by the heavy rainfall in the river basin, and provide various impacts, depending on its magnitude and frequency. This research aims to evaluate the magnitude and frequency of extreme freshwater discharges, and to establish the magnitude-frequency relationships between basin-wide rainfall and freshwater inflow. Daily discharge and daily basin-averaged rainfall from Jan 1, 1997 to Aug 31, 2010 were used to determine the relations between discharge and rainfall. Consecutive daily discharges were grouped into independent events using well-defined event-separation algorithm. Partial duration series were extracted to obtain the proper probability distribution function for extreme discharges and corresponding rainfall events. Extreme discharge events over the threshold 133,656,000 $m^3$ count up to 46 for 13.7y years, following the Weibull distribution with k=1.4. The 3-day accumulated rain-falls which occurred one day before peak discharges (1day-before-3day -sum rainfall), are determined as a control variable for discharge, because their magnitude is best correlated with that of the extreme discharge events. The minimum value of the corresponding 1day-before-3day-sum rainfall, 50.98mm is initially set to a threshold for the selection of discharge-inducing rainfall cases. The number of 1day-before-3day-sum rainfall groups after selection, however, exceeds that of the extreme discharge events. The canonical discriminant analysis indicates that water level over target level (-1.35 m EL.) can be useful to divide the 1day-before-3day-sum rainfall groups into discharge-induced and non-discharge ones. It also shows that the newly-set threshold, 104mm, can just separate these two cases without errors. The magnitude-frequency relationships between rainfall and discharge are established with the newly-selected lday-before-3day-sum rainfalls: $D=1.111{\times}10^8+1.677{\times}10^6{\overline{r_{3day}}$, (${\overline{r_{3day}}{\geqq}104$, $R^2=0.459$), $T_d=1.326T^{0.683}_{r3}$, $T_d=0.117{\exp}[0.0155{\overline{r_{3day}}]$, where D is the quantity of discharge, ${\overline{r_{3day}}$ the 1day-before-3day-sum rainfall, $T_{r3}$ and $T_d$, are respectively return periods of 1day-before-3day-sum rainfall and freshwater discharge. These relations provide the framework to evaluate the effect of freshwater discharge on estuarine flow structure, water quality, responses of ecosystems from the perspective of magnitude and frequency.